In my opinion, based on my experience in this game, the game gives hidden advantages to certain teams itself (some as early as at the start of the season) so that those teams have a significant chance to win a particular competition (the competition that the game will be favouring this team). Then, it is all about that favoured team. If that team has the basics (decent squad and formation) and certain minimum requirements, it goes on to win that competition even if there are stronger, active teams in that same competition. Tactics and so on, all seem to fail when you face such a team as the game wants that team to win that competition this season. One of the only way to counter this is to have extremes in quality, that is very large quality advantage, where this advantage overrides the effects of the hidden favours given by the game. On the other hand, if that favoured team don't even have the basics or do not have the minimum requirements, then it won't win that competition, else you would have been seeing lots of weak, abandoned teams with messy formations winning the competitions,
In another way to say this, it is like there is something in the game that sets which team will have a good season, which team will have a good season with respect to what competition, things like that; there is a sort of hidden pluses (+) or minuses (-) already attached to teams from the start of the season itself.