Oh, Prufrock, why didn’t you just go into your lover’s "chamber" and ask her your darned "overwhelming question" when you had the chance?! Prufrock is the dramatic equivalent of a bump on a log. He never does anything. In this poem, no one does. Actions are discussed as either future possibilities or as thing already done and past. And not for a second do we believe that Prufrock has "known" all the things he claims to have known. The only thing this guy is good at is eating and wearing nice clothes.
The entire poem is one big, long digression so that Prufrock doesn’t have to tell his life story.
Prufrock’s passivity is dangerous because it makes him hold tightly to the status quo. He is willing to go to great lengths to prevent things from changing.