James Gill has a good overview of How bad features are born:

Most importantly, does this feature deserve to exist? Why are you working on it?

If you’re embarking on a new feature primarily because you’ve seen a competitor release something similar, then you probably haven’t thoroughly considered or even identified the problem you’re trying to solve. If you’re jumping into a new feature because it seems like “it wouldn’t be too hard to do” that’s great, but does it actually deserve to be built right now?

The biggest danger I see is this “it’s easy to implement” argument. A feature might be easy to implement, but that doesn’t make it “cheap”. The problem with implementing even easy features is that they’ll most likely remain in the product forever. That creates the potential for lots of (expensive) maintenance and support.

Also see How Much Does A New Feature Cost?