The exact time to quit something is always a personal decision for the individual
. As I've explained, the easiest time is actually before you even start but it's never an easy decision to make. However, the simple action of evaluating your project can identify flaws and weaknesses that potentially make it impossible, or very unlikely to succeed. It takes courage, but it may be a good time to take the bold step of moving on to something that will offer you the rewards you deserve for your hard work.