How can a 40 watt amp outshine a 140 watt amp


My query is; I see $6,000 integrated amplifiers with 40 watts per channel, how is this better than my Pionner Elite SC-35 @ 140 watts per channel, what am I going to hear different, with a, let's say Manley Labs - STINGRAY II? I obviously don't understand the basics involved and if someone could explain or point me in the right direction, I would greatly appreciate it.

I would like to set up a nice two channel analog system. I really can't afford the aforementioned Stingray, what is "out there" in the 2.5 grand range?
mystertee
Easy: connect a 40 watt rated light bulb to each amp. Run a 50/60 hz sine wave at 2 to 3 volts rms into each amp. Eventually the 140 watt amp will blow the light bulb. There you have it. The 40 watt wins.
Thanks Gs5556 and Dpac996 for some very useful insight. I have a lot to learn, but it's going to be fun and I think AudiogoN will be THE place for my education.
"If you can't hear it, then no reason to invest in better amps!" by Grannyring.

Now there is a quote and a half! Let that guide you thru the Sea of Snake Oil.

I'll add that while navigating thru that sea, there may be differences that you won't hear the first tune but will, upon further listening, become apparent. If those differences are worth it to you then go for it. Vote with your wallet.
I just don't understand why it is that we all love this hobby if so much of it is truly unbeievable. As in "Snake Oil" etc. fixed delusions. I think we all believe that there are real differences in some aspects of audio or else we would join the silent majority of listeners content with whatever they use for sound reproduction.