Usually because the **manager is using a standardized LPA** and only a subset of LPs have enough leverage, legal requirements, or special circumstances to justify changes.

- **Most LPs sign as is** because:
- the LPA is meant to be consistent across all LPs
- uniform terms reduce legal and operational complexity
- customized rights can create fairness concerns

- **Some LPs comment or negotiate** because:
- they are larger check writers
- they have institutional counsel
- they need specific tax, regulatory, or compliance accommodations

Those LP-specific changes are often better handled in **side letters**, not by rewriting the main LPA for everyone.

References:
- https://decilegroup.com/articles/vc-fund-legal-structure-explained
- https://decilehub.com/base/1-general_questions/163991-why-does-the-lpa-now-restrict-side-letters-that-give-favorable-treatment-to-certain-lps