> Whoops, another team made a bunch of commits to their project, and you need to rebase your project before you can commit. If their commits didn't affect you,

> Whoops, another team made a bunch of commits to their project, and you need to rebase your project before you can commit. If their commits didn't affect you, then … it merges cleanly, and you don't care. If their commits do affect you, then … now you know. With multiple repositories, you will have no idea that they broke something you rely on. Even better, with a monorepo, if they break something your existing code relies on, they' have broken the build, and they have to fix it. With multiple repos, another person or team is free to break things you rely on without even knowing it, and you won't know it until you update your dependencies hours, days, weeks or months later, wondering why everything is suddenly different. If another team's work is tightly-enough interwoven with yours that their daily commits affect you, then you're all on the same team (and/or your architecture needs work).