The first year he didn't improve them, the second year was far better but they still only managed 4th by 1 point above an Arsenal that was free-falling under Wenger. Knocked out of the cups by Southampton and Wolves and dumped out of the Europa that year too. Once Mane and then Salah came in and their long ball to the pacy winger tactics took shape they kicked on.
It wasn't an overnight thing and it took Klopp two very good transfer windows to build the team to play the way he wanted.
@GwladysBlue making out like Klopp walked in and made them title contenders from day 1 and then using that as a stick to beat Ancelotti with is a bit of a joke imo.
That first year there were many kopites that were not convinced he was a step up on Brenda. A lot of things went their way during the early Klopp period, the declines of Arsenal, Utd, Tottenham, and Chelsea, the ridiculous fee they got for Coutinho, etc.
He's a good manager and has definitely improved them but it still took time and that is what we need to give to Ancelotti.