It is always a good idea to set concrete targets whatever you do. If you have those targets (KPIs if you wish), you will know when to quit. Your goal can be 10

It is always a good idea to set concrete targets whatever you do. If you have those targets (KPIs if you wish), you will know when to quit. Your goal can be 10 or 100 paying customers by the end of the year, it doesn't really matter, you just have to make conscious decisions whether you are okay with those numbers.