Lopetegui ready to learn from mistakes ahead of League Cup trip to Liverpool
Lopetegui's men lost 3-0 to their London rivals on Saturday, with the 58-year-old Spaniard under fire for his tactics and team selection.
The former Spain and Real Madrid boss replaced Guido Rodriguez before half-time and later admitted he had erred in starting with the Argentina midfielder.
"We learn a lot from our mistakes," Lopetegui told a pre-match press conference on Tuesday.
"But let me just say one thing. When you win you make mistakes too. When you lose you make mistakes. This is football.
"One thing that I say, that I make one mistake - and I have talked about this. Mistakes are a part of football.
"The more important thing is that we are able to do better. We have (made) a big commitment with the players, knowing that the most important thing is at the end of the season."
West Ham, beaten in the League Cup quarter-finals by Liverpool last season, have lost all three home league games this season under Lopetegui, who replaced David Moyes in May.
The Hammers are currently 14th in the table, with four points from two away games - a 2-0 win at Crystal Palace and a 1-1 draw at Fulham.
"I told the media after (the Chelsea game) that the first person responsible was me. Always," Lopetegui said. "It happened and now we are focused on the next match.
"Mistakes are made by the coach. They are part of football because we make decisions - sometimes better, sometimes worse.
"But we have to keep making decisions to help the team to compete better. I am sure that the team is going to compete better and is going to arrive at the results and scores that we want."