Brock Lesnar invaded the Money In The Bank match towards the end of the event and won the match, earning the MITB briefcase. WWE needs to increase their ratings for the product, so they decided to use Brock Lesnar to help with that.
The Wrestling Observer Newsletter reports that the scripting of the match was done in a way to to draw heat on Lesnar after his win. The other competitors were taking huge bumps in order to win and then Lesnar got to run in without taking a bump and win the match.
The main part of their reasoning was to increase the ratings for RAW the next night and the week to follow where Brock will reveal what he’ll do with the MITB contract.
It was all about a momentary pop and surprise, as well as two weeks of television ratings. The feeling was that the Lesnar surprise would help ratings based on curiosity the next night, which it did.
It will be interesting to see what Lesnar does next week on RAW.