I'm very particular when it comes to finishing. Most of my sanding is done with cabinet scrapers and depending what I'm working on I'll follow through as high as a 5 micron grit.
Most will start with a 100 and follow through with 220, 320,400 and most times this is satisfactory prior to applying the finish. Others like myself will go further. So when it comes to sanding it depends on what you're satisfied with. There are no rules.