This is a very similar path to the one that Skitch and Dropbox took. In each case, instead of perfecting and maintaining a really good app, business pressures caused them to pursue growth at all costs. This is a common problem these days.
The problem is that the PMs are incentivized to deliver features, even if that is not the right thing to do.
See: Postman.
If a PM is just delivering features without tying it back to user needs, business growth & product strategy then they are just a "feature factory" which is bad product management.
You mean greed.
- Increase prices - which will drive some of your customers away.
- Revenue through ads - which will drive some of your customers away.
- New products - risky, and if successful it sometimes means the original product becomes abandonware.
- New features to try to increase the audience for your product or monetize directly - what it seems like Evernote did.
But not every product can have billions or even millions of users. So sometimes these all fail anyway. Basically investment, whether from VCs or an IPO, is often death for a small business serving a niche market.