One practice I really like with Feature Flags is having a flag budget. Building on the idea of an error budget, where some percentage of errors is okay, but at a certain threshold feature work needs to slow or stop to get it under control.

Having a limit of in-flight feature flags, means you’re incentivised to clean them up when they’re done (or decide they’re long running features etc), and it can help keep a handle on in progress work.

But mostly, feature flags are a powerful tool—they can hurt as much as they help if you don’t use them right.