One thing I have seen a few times is a main character in a book being the first to do something that should have been done well before hand.
For example, if I was writing a book about the invention of a replicator I would expect that it would take about a week for someone to note the many ways it can be used as a weapon. Or use it to make drugs. Or for that matter to have it create an explosive that would be so unstable it normally could not be moved, therefor used.
If your character is the first person to do something, think about WHY this is the case. Would they really be the first ones?