It seems that Juventus understands which is more important in their two meetings because in Serie A it could be said that there is no longer any chance for Juventus other than remain in the top four, and the Coppa Italia is important to maintain their chances of getting the title this season.
I don't think that Juventus would be able to score two goals but they did it and Lazio didn't score a single goal giving an advantage to the home team, Lazio didn't even have a single shot on target so it could be said that Juventus' goal was relatively safe from Lazio's attacks this time.
With a two-goal advantage, Juventus has the opportunity to go to the Coppa Italia final, because Lazio has to score three goals and in my opinion, that is quite difficult if we look at Lazio's poor attack this season with only having an average of 1.xx goals.