That is a really hard question to answer because there are different kinds of pumps. It might be a poor producing well needs a new pump, so does that make it a bad well? I had a client go from 3 gals/min to 12 when they replaced their pump.
Most people like to see at least 12-15 gallons per minute in a four hour flow test in my area, but honestly in some of the more difficult water areas, 5 gallons per minute might be a great well, for that particular water vein. Anything over 30 in my area is considered a gusher of a well. You can have two acreage properties right across the street from each other and one will gush at 30 gals/min and the other will trickle in at 3. It just depends on what water vein you are in.
You need to focus on what is normal for your area.