AC Milan is trying to build a team quickly, a practice they typically employ by combining senior and junior players. While the success rate isn't high, AC Milan has had success in the past two seasons, though not as impressive, considering the team's structure, it can be considered a success.
It's not easy to build up a winning team quickly but AC Milan certainly are trying to build up their team stronger at as fastest speed as possible. They are a second most successful club in Italy, after Juventus, so they always have ambition of winning Scudetto but I think AC Milan are realistic that they are not strong enough to win this title in a new season.
If I'm not mistaken, AC Milan and Roma were the only Serie A teams that took their preseason games seriously, the rest of the teams did not, perhaps because they did not see it as a game that would help them prepare for league games. Come also took the preseason games seriously, winning the three games they had played against Lille, Al Ahli, and Ajax, but this doesn't mean that they would perform well in the league.
They failed in the last season and could not get in top four so they don't want to repeat that failure this season. By hiring two experienced coaches, Gasperini and Allegri, both AC Milan and AS Roma will have very ambitious targets for a new season and they will try to play as best as possible match by match, and adjust their target gradually over time and matches.