Neglect
The villian kidnaps one of the heroes companions, the one they think is the most valuable asset, since they do all the research and is quite clever.
The companions repeats a few times that no one will come for them, that the villian chose the wrong person to kidnap and should've kidnapped the heroes love interest or whatever instead.
The villian doesn't listen, insists that the companion is the most important part of the hero's little team and thus of course someone will come for them ...
After 2 weeks, the hero hasn't shown up and the villian, having had a history of neglect and lonlieness, is so fed up they show up the heroes doorstep to yell at them.
















