A significant part of my job, unfortunately, is helping people fix their workspaces when Perforce (p4) goes bad, or creating guardrails and wrappers to stop Perforce doing bad things.
In fairness, p4 predates most of the VCSes we consider "modern", so I empathize with a lot of the underlying architecture decisions. However, it has and continues to utterly fail at improving at a reasonable pace.
For example:
- p4 tracks file metadata of client workspaces on the server (sync'ed locally, opened for edit, file revision, etc) and uses this as the basis to avoid doing unneeded work. If this becomes desync'ed, a reconcile or force sync must be used. A reconcile can take hours, potentially days; it tries do detect file moves by default, so likely at least O(c^n) for some c>1. I have never personally seen a default reconcile operation _complete_ over any modestly large game code base, and in practice, people accumulate a litany of workarounds and scripts to fix this for themselves.
- Scripting p4 is a nightmare. Documentation is poor, schemas do not exist, and all the language-specific libraries are just thin wrappers over its C++ API.
- By default, p4 "helps" you with text files by "correcting" line endings on sync or even converting between encodings. This works until you have a mixed-OS environment, and discover a part of the pipechain that _must_ have a certain style. There are various levers to pull to make this better, but I've yet to find something fool proof.
- By default, p4 keeps flies read-only, only unlocking them when explicitly marked as being edited. This means, to avoid having to do this manually, every tool you use needs to be p4-aware. Or, you can turn this off, and choose to contend reconcile instead. (See above)
- Branching a modest game project, with, say, Unreal source code, can take hours. And this is the quick version where you ask the server to simply create new metadata, with no file transfer to a client.
- p4 is licensed by the user-account. Every user entity in p4 not intended exclusively for performing backups and maintenance operations counts toward this, including users required to integrate with other services. Plus, often times, these integration users must have admin access to be useful. The security posture is horrific.