Microsoft 365 Copilot: strengths, limitations, and when to use it
Microsoft 365 Copilot has become the default AI assistant for organizations living in the Microsoft 365 universe. At the same time, in many enterprises, it’s hitting its limits. This article clarifies what Microsoft 365 Copilot does best, where it reaches natural limits, and how it compares to alternatives, so you can decide which solution fits your use cases and governance requirements.
What Microsoft 365 Copilot is and how it works
Microsoft 365 Copilot is an AI-powered assistant integrated into Microsoft 365 apps like Word, Excel, PowerPoint, Teams, and Outlook. It uses LLMs combined with your organization’s data to boost productivity by generating content, summarizing information, and automating tasks.
Let’s define the most important terms of the Microsoft Copilot universe:
- Microsoft Copilot 365: An AI assistant embedded in Word, Excel, PowerPoint, Outlook, and Teams; this is what people usually mean when they talk about Copilot – the “ChatGPT for the office”.
- Microsoft Copilot Studio: A low-code platform to build, customize, and govern your own /agents and plugins. It lets you connect to data sources, define actions, and ground responses on your content (a Retrieval Augmented Generation, or RAG, approach) using connectors, websites, files, and enterprise systems
- Azure AI (including Azure OpenAI service, Azure AI Search, and Microsoft Foundry): A cloud platform for building custom AI applications. For RAG solutions, you typically combine Azure OpenAI models with Azure AI Search (vector and keyword search) and your own content stores, orchestrating the workflow via Microsoft Foundry for prompt flows, evaluation, and deployment.
Use cases of Microsoft 365 Copilot
Use cases that are perfect for MS 365 Copilot: the tool shines in simple, straightforward use cases, such as:
- Drafting, rewriting, and summarizing in Outlook and Word
- Analyzing trends, creating formulas, and building charts from natural language prompts in Excel.
- Generating slides, designing presentations, or reorganizing content based on prompts in PowerPoint.
- Summarizing chats and meetings (up to 30 days), extracting action items, or answering questions from transcripts in MS Teams.
Use cases that tend to be challenging with MS 365 Copilot:
- Bridging data silos and making knowledge distributed across multiple systems outside the Microsoft environment accessible, particularly where identity and permission mapping are complex.
- Gathering data from and transferring data between different systems.
- Use cases requiring the highest precision and prevention of hallucinations, e.g., for critical processes.
- Handling critical, sensitive company data in the regular version (works in the company version)
Strengths of Microsoft 365 Copilot
Like any tool, MS Copilot shows strengths as well as limitations. Let’s have a look at where it performs very well:
- The tool works nicely for users who live entirely in the MS universe: It’s ideal for users who navigate between MS Office, Outlook, and other relevant Microsoft tool interactions.
- It’s ideal for beginners: MS 365 Copilot is perfect for beginners and simple workflows: Low friction and minimal context‑switching for Microsoft 365 users.
- Quick setup: Copilot is available by default and can be used instantly.
Limitations of Microsoft 365 Copilot
MS 365 Copilot comes with some challenges, and some organizational use cases might be challenging to tackle with MS Copilot.
- SaaS only: Copilot is a cloud service; there is no self‑hosting or on‑premise deployment option, and no customer‑managed LLM deployment. Microsoft provides data residency commitments for “content of interactions,” including Advanced Data Residency (ADR) and Multi‑Geo, but notes that LLM calls can route to other regions under high utilization. Scenarios using Anthropic models are currently not covered by the EU Data Boundary.
- MS Universe only: MS 365 Copilot is strongest with Microsoft 365 content. It can incorporate external systems via Graph connectors and agents, but the breadth and depth depend on available connectors, identity alignment, and admin configuration. Deep integration to bespoke or legacy systems typically requires additional integration work outside Copilot itself. Thus, at a specific point, organizations need to involve development experts to take care of those integrations.
- Unstructured or overshared data needs governance first: Copilot’s quality depends on your existing information architecture and permissions. Microsoft recommends strengthening governance—reducing oversharing, cleaning up unused sites, setting owners, and using Purview sensitivity labels—to improve appropriateness and accuracy. Copilot itself doesn’t replace data engineering or content curation.
- Strict sovereignty or on‑prem constraints: Even with ADR/Multi‑Geo, Copilot remains SaaS; certain LLMs calls may be processed outside your local geography under load, and some model providers fall outside the EU Data Boundary. Organizations needing fully EU‑local or on‑prem LLM processing will see limitations here.
- Service evolution: Microsoft regularly updates foundation models. While privacy/security settings remain, behavior can change, so teams should monitor and adapt prompts/processes over time.
Alternatives to Microsoft 365 Copilot
Copilot is an excellent, fast-to-adopt SaaS for enhancing general productivity, but it’s not always the best fit for every organization’s requirements or workflows.
Organizations should consider an alternative platform when their use cases demand deep domain tailoring, custom guardrails, or tight integration with non-Microsoft systems and proprietary data pipelines and infrastructures.
For businesses operating in highly regulated industries, residency or data segregation requirements (e.g., private cloud, on‑premises, or customer‑managed encryption and detailed audit logging) often demand solutions with finer-grained security and governance controls. Companies prioritizing total operating cost, throughput predictability, or model choice flexibility may benefit from more customizable platforms that offer deeper control and optimization. In short, when precision, compliance, and infrastructure control matter more than turnkey convenience, exploring Copilot alternatives is the pragmatic next step.
ONTEC AI as an alternative to Microsoft 365 Copilot
One example is ONTEC AI.
ONTEC AI is a European, model‑agnostic AI platform designed for sensitive and complex data. It provides RAG‑based enterprise search, a private “Company GPT,” and AI agents that automate multi‑step workflows across IT systems.
ONTEC AI integrates with Microsoft 365 and beyond (e.g., SharePoint, Confluence, file shares, SAP/custom ERPs/CRMs, and identity providers and authentication protocols like Entra/AD/LDAP/SAML/OIDC).
ONTEC AI’s RAG approach is designed to reduce hallucinations and expose reliability measures; it is model‑agnostic across Open-AI‑family models, Llama, Mistral, Aleph Alpha, and more to avoid vendor lock‑in.
ONTEC AI includes granular data governance (authentication, role‑based access, anonymization) and can be deployed in the EU cloud or fully on‑premise for maximum sovereignty.
Side‑by‑side comparison: Microsoft 365 Copilot vs. ONTEC AI
Let’s directly compare MS Copilot with ONTEC AI as an alternative:
| Microsoft 365 Copilot | ONTEC AI | |
| Type | Standard software | Individual, domain-specific, and tailored to use case |
| Data | Simple data | Complex and sensitive data |
| Accuracy of data retrieval | medium | High due to strong hallucination suppression |
| Integration | MS Office: Word, Excel, PowerPoint, etc. | Cross-platform; all data formats and integration in SC-Systems |
| Delivery and hosting | SaaS in Microsoft’s cloud; no self‑hosted option | Flexible hosting: EU cloud or fully on‑prem/self‑hosted |
| Ecosystem scope | Native to Microsoft 365; can add external data via Graph connectors and admin‑approved agents | Integrates with Microsoft 365 plus Confluence, file shares, drives, SAP/custom ERPs/CRMs, and more |
| Update cadence | Microsoft controls service/model updates; behavior evolves over time | Customer‑tailored deployments and roadmap; controlled change management |
| Data security | Ok; data centers in Europe available | High |
| Data sovereignty | Data residency commitments for “content of interactions” (ADR, Multi‑Geo); LLM calls can use other regions under load; some models outside EU Data Boundary | EU‑based provider; GDPR‑compliant; supports full on‑premise deployment and granular governance (RBAC, anonymization) |
| Adaptability | Strong UX within the MS universe; extensible via connectors/agents; complex workflows may require admin/dev effort | Designed for custom/legacy landscapes; AI agents execute multi‑step workflows end‑to‑end |
| Models | Primarily OpenAI models and, in some scenarios, Anthropic models | Model‑agnostic: GPT‑models, Llama, Mistral, Aleph Alpha, etc.; multi‑LLM and reasoning layers across models can be chosen freely |
| Out‑of‑the‑box vs. setup | Rich “basics” in Microsoft apps; advanced scenarios need configuration, connectors, agents, and potentially Copilot Studio/Power Platform | Requires setup aligned to your systems; PoC‑to‑production path with ONTEC AI services; deep integrations available. |
| Emphasis | Speed and convenience for knowledge workers; user‑reviewed drafts and summaries | Precision for sensitive/complex data via RAG; explicit hallucination suppression and reliability metrics |
| Use‑case sweet spot | Simple to moderate workflows inside Microsoft 365 (documents, emails, chats, meetings) | Sophisticated cross‑system use cases, enterprise search across silos, full workflow automation via agents, and critical processes |
| RAG | For a RAG solution, standard components need to be added via Azure AI | available |
Decision guide: When to choose MS 365 Copilot, when to use alternatives like ONTEC AI?
So, when to choose what?
Choose Microsoft 365 Copilot if:
- Your users fully live in the Microsoft 365 universe, and all your data lives on the Microsoft ecosystem.
- You want rapid productivity gains in everyday, straightforward tasks (drafts, summaries, meeting recaps)
- Your governance and permissions in SharePoint/OneDrive/Teams/Purview are mature, and you’re comfortable with SaaS‑based AI under Microsoft’s data residency commitments.
Consider alternatives like ONTEC AI if:
- Your knowledge is scattered across Microsoft and non‑Microsoft systems (including bespoke/legacy apps),
- You require high‑precision actions, reasoning transparency, and AI agents that can execute multi‑step workflows end‑to‑end.
- You need strict EU/GDPR controls, up to full on‑premise deployment, or must avoid LLM vendor lock‑in with a model‑agnostic approach.
Conclusion
Microsoft 365 Copilot is excellent at accelerating everyday work inside Microsoft 365—drafting, summarizing, and surfacing context that a user already has permission to see. ONTEC AI complements or substitutes for Copilot when you need EU‑centric deployment (including on‑prem), model choice, deep integration with non‑Microsoft and legacy systems, and precise, RAG‑grounded answers—plus AI agents that go beyond analysis to real execution.
If your organization is considering one, the other, or both in combination, start by mapping your data landscape, sovereignty requirements, and workflow complexity. Many teams adopt Copilot for rapid productivity inside Microsoft 365 and pair it with ONTEC AI for enterprise search and cross‑system automation, where accuracy, sovereignty, and adaptability are paramount.
FAQ
What are the limitations of MS 365 Copilot?
Microsoft 365 Copilot is cloud‑only with no on‑premise option; under high utilization, some LLM calls may route to other regions, and certain model scenarios are outside the EU Data Boundary. Its effectiveness depends on existing Microsoft 365 information architecture and governance—Microsoft recommends reducing oversharing, cleaning up sites, and using Purview sensitivity labels—so Copilot does not replace data engineering or taxonomy work.
Copilot is strongest with Microsoft 365 data; bringing in external systems requires connectors/agents and proper identity/permission mapping, and deep bespoke integrations typically need additional work outside Copilot. Microsoft also notes outputs aren’t guaranteed to be 100% factual and should be reviewed, and foundation model updates can change behavior over time.
Is ONTEC AI an alternative to Copilot 365?
Yes, ONTEC AI is an alternative to Copilot and especially relevant in specific use cases. Microsoft 365 Copilot is a SaaS assistant embedded in Microsoft 365 apps and grounded in Microsoft Graph, delivering quick productivity gains (drafting, summarizing, meeting recaps) while honoring tenant permissions and Microsoft Purview policies.
ONTEC AI is a European, model‑agnostic platform built for sensitive and complex data with RAG‑based enterprise search, a private “Company GPT,” chat with documents, and AI agents that automate multi‑step workflows across systems. Copilot can extend to some external systems via Microsoft Graph connectors, and admin‑approved agents, whereas ONTEC AI integrates deeply with Microsoft and non‑Microsoft/legacy environments and identity providers.
For sovereignty, Copilot offers data residency commitments for “content of interactions” but remains SaaS, while ONTEC AI supports EU cloud and full on‑prem deployment with granular governance.