I was bored and made this table. Sure there is something else like it, but here you go.
The Shadowrun “Whats Goes Wrong With The Mission”
Roll 2d6 at the begging of the mission
2 : An opposing shadowrunner shows up after same objective
3 : Police or corp security heard about the run and set up a trap
4 : The objective was recently moved to a different location without the runners knowing
5 : The security is extra tight due to a recent break in
6 : There is a new security feature not discovered in the briefing or legwork
7 : There are no unexpected wrenches in the works, or terribly faulty data(standard run)
8 : Johnson either omits a key piece of info or gives false info(intentionally or not, GMs choice)
9 : Johnson puts an unreasonable extra objective that will lower pay if not completed
10 : The run was part of a much bigger set up, and the runners may end up in hot water for being involved
11 : Johnson either runs away or tries to get out of paying the runners.
12 : It’s a trap! Johnson is trying to get the runners killed/captured.