Liverpool, which had a tough 4-3 victory over promoted Leeds United to start the new campaign, bolstered its squad on Thursday with an agreement to sign Spain midfielder Thiago Alcantara from Bayern Munich, Reuters reported.
"It's completely normal that we have to make another step because other teams will make other steps as well," German Klopp told Sky Sports.
"It has nothing to do with being champions, we constantly try not to develop but to find solutions to the new challenges before we have the problems with them.
"But a lot of the good things we did, first and foremost we have to show again, so it's not only about changing things it's about finding the right approach and plan again for this season."
Liverpool visits Chelsea in the league on Sunday and Klopp said Frank Lampard's side has quality all over the pitch.
"There's plenty of threats, they've signed really well and already had an unbelievably good team," Klopp said. "We had to suffer a lot against them in the games last season.
"There's so many good players up front, in midfield, the defensive line and the fullbacks – there's not a biggest threat, Chelsea themselves are the threat."