There’s an old adage in video and film production. When you think you’ve shot enough, shoot a little more. That’s because you never know what might come in handy in the edit room. Better to have too much raw material than not enough.
It’s actually a concept that translates well to just about any field. Don’t do just enough work to get the job done, go beyond that so you have plenty to do a great job.
Usually doing just enough work will get you paid, it just won’t get clients to return.