First of all, to offer a contest for your downline, you need to be able to follow through on your promise.
Contests can be for 1st level PSAs, CSAs and/or go down many levels.
There are many benefits for contests, mainly motivating your entire downline to do their very best:
1. Your affiliates will see how well they are doing and want to continue. (PSA or CSA)
2. They will see their own downline do better if the contest goes down several levels. This will motivate them to keep going so they don't lose out on commissions. (for PSAs)
3 They will also begin to like and trust the Upline who is so generous and caring. They will want to follow someone whom they know and trust.