"Quality counts" is a nice meme, but without specifics it lacks usefulness and can even be misguiding. There are many forms of quality. Some are vital when launching an app, others should be pared back if doing so allows you to launch earlier or provide better core features.

The real trade off with Quality is not profit but iteration speed. Every feature you include has a quality scale from 1-10. A '1' is going to be barely usable and will frustrate users, a '10' can take months to achieve and your feature or app may be irrelevant by the time it's done.

Picking the right value to hit will depend on your market, your users, and your resources.