Todays daf in Bava Mezia 105 had an interesting situation. There is an iska partnership which means that one person provides capital and the other does the work. The agreement is pursuant to a deal, a contract or a period of time. When one partner wants to roll over profits and continue and the other person dosent, what happens? The Talmud says that the partner must continue. The reason is beautiful. The Talmud says, Mazel of two people is better than Mazel of one. The notes in the arstcroll imply that each one brings a strength, a talent or some unique quality which complements the other.
This speaks volumes. There are probably a million ethical or moral lessons to be learned. The simple or most basic is that all profits, success is Mazel or divinely provided. The extension of this divine gift is that Gd wants us to work together.