The Argentine feels Alli has turned a corner after a patchy run in late 2017, and has tipped the midfielder to return to his best.
"Dele has been good in the last few games, he's started to improve," said Pochettino. "And we've started to recognise the player again who has achieved so much in the last two seasons.
"For me there's no doubt about his quality and potential. But because he's young, he needs to breathe sometimes, take some time, then again perform in the same way.
"From day one when he started to play here at Tottenham and achieve, not one other young player of his age [has achieved as much]. Not Cristiano Ronaldo, not Frank Lampard, not Wayne Rooney, massive players, great players - he has achieved more than all those big names.
"The problem is the expectation. We expect from him in every touch, every action, unbelievable things. And sometimes that's not possible."