I know two person, in the similar business, one is doing project after project, and is high rich now, not big but in 5-10 million range, with life time of hard

I know two person, in the similar business, one is doing project after project, and is high rich now, not big but in 5-10 million range, with life time of hard work. The other person, did only two big projects in similar life time. Both retired now, the other one has about 15-20 million. Waiting for the right opportunity paid off really well, along with hard work.