Insightful.
Why not all three..., OK well, at least two of the choices? Seriously, I bet because I think I have the best hand, which also gives me value & protection if he calls when behind PLUS I want to represent more strength than I actually have.
You raise pf and on the flop you have a weak top pair hand on a draw heavy board that is all over villains pf calling range. Whether you currently have the best hand is not clear just yet.
You may well be ahead and often you will have the best hand currently yet have as little as 45% equity with 2 cards to come.
against a wide continuing range like...
TT-66,QJs,Jc9c,Tc9c,Tc8c,9c8c,8c7c,8s7s,7c6c,QJo,JTo,T9o,98o
we have 52% equity, in position this plays out a lot easier but oop and likely facing a competent opponent. Pot control is my main objective and folding to any significant action can never be too big a mistake and is more often correct. In summary, villain is in control of pot size throughout the hand and if it the pot gets big, its because he wants it that way.
I want to represent more strength than I actually have.
Villains calling range contains X% hands that beat us and Y% hands we have value against, the ratio of X:Y is largely dependent on the strength we represent, this is a basic poker concept.
representing more strength than I actually have = Bluff