Chelsea have now lost five of their last eight Premier League matches, leaving their manager questioning their ‘desire’ and admitting it was natural that his own position would come into question.
Goals from Wilfred Ndidi and James Maddison saw Leicester climb to the top of the table, while the visitors are left nine points adrift.
Lampard said: “The players know they were beaten by a better team tonight. A team we competed with until the end last season and that we are points behind.
“The general theme of our performance was slower, sluggish, lacking in desire to run. When a team is confident, they look like Leicester or we were a month ago.
“I wouldn’t say they’re letting me down, but there are players who are not playing as well as they should be.
“It is a fact of where we are as a club. If you look at the composition of the squad, young players or ones who were on loan or in the Championship.
"It’s asking a lot for them to become John Terry overnight. To find consistency and find that is the next level for us.”
On his future, Lampard added: “It intensified for me a while ago. Expectations at this club are high.
"Right or wrong. When we perform like that it is normal people will ask questions.
“It is not my decision. That is something that will always be there.
"Some things are always beyond your control. That I can’t answer.”