Milan went into Friday night's clash hit hard by injury, but managed a 1-0 win thanks to Tijjani Reijnders' goal.
“The first half was somewhat inevitable with so many players missing and not winning the most recent match, so we were sluggish,” Fonseca told DAZN.
“It’s true that we did not allow Verona much and dominated possession, but without being aggressive in the final third. We made too many wrong decisions, that is also down to a lack of confidence, because we had the ball so often near the penalty area and should’ve done better.
“As I said, without so many players at the moment and our current form, I am satisfied with the victory, which was the most important thing. It was a much-deserved win, we kept a clean sheet and showed more stability in defence. We need to improve in attack, but that’s our current moment affecting confidence.
"The centre-backs did very well, so did (Youssouf) Fofana and (Filippo) Terracciano in midfield when shielding the defence. This stability is important to have so that we can then attack with more confidence. I am seeing increased stability in every game.”