Young Justice: Invasion aka Young Justice Season 2's story started 5 year after the conclusion of season 1. Why is this sudden 5 year gap between the story? Did the officials talk about their reasons?
This is taken from the Station Eight fan site. It's a quote from Greg Weisman, one of the show's head writers.
Greg Weisman says:
"While developing Season One, we had a solid idea of what we had in mind for Season Two - including the time skip. And we had/have solid ideas for Season Three, including another time skip."
[Response recorded on July 17, 2012.]
"We planned on this time jump from day one. Because we knew, again, that if our show's about growing up, then you can't show a character grow up in 6 months' time. So the idea is that our first season told 6 months from July 4th to January 1st. Our second season tells another 6 months from January 1st to July 4th, but there's a 5-year gap in-between that we planned."
If you analyze the characters post-jump, you'll see that they have matured and do behave differently, and this isn't something that could be accomplished realistically in even an entire extra season. The show the progress of the Team, and show the results of the track they were headed on, it was necessary to skip forward in time.