Star Trek: 10 Worst Things Captain Janeway Has Ever Done
1. Altering History Because She Doesn't Really Like It (Endgame)
Exactly what right did Admiral Janeway have to alter history, thus changing the lives of everyone in existence, during the events of Endgame? That is a question that the Admiral doesn't seem to consider as she steals the temporal device from Korath and takes her shuttle into the past.
Her actions may be coming from a place of love - she is concerned with getting her crew home safely after all - yet she is potentially condemning trillions of lives to a different fate in doing so. Consider the argument that Captain LaForge made to Chakotay in the episode Timeless - he can understand the former commander's actions, but he has to act to save history.
Who is to say that history didn't play out exactly as it was meant to? Who is to say that Seven of Nine was supposed to survive at all? Her actions may have saved lives and dealt a crippling blow to the Borg, but Admiral Janeway proved that her own motivations meant more to her than the entirety of reality.