When using a power conditioner, why is it advised to run amps directly to the wall?

My personal experience with power conditioners.  For years and years, I ran all my amplifiers straight into wall outlets (using upgraded audiophile wall outlets).  I plugging my amps straight into the wall outlets, and not into power conditioners, because it was the prevailing wisdom in the high-end audio/audiophile community, so I just followed suit and went along with the crowd.  But one day while visiting one of my local high-end audio shops (who sold mega-buck caliber audio gear), I was introduced to a non-power restricting power conditioner that actually enhanced the sound by just removing the noise and grunge, while actually not restricting it’s power or current.  I was so impressed by what I heard from that power conditioner, I was inspired to investigate further, so I began experimenting with that power conditioner, the one I heard at the high-end audio shop, and also various other power conditioners that were advertised as non-power restricting.  In the end, and after extensive and exhaustive A/B comparisons, I found that I got better result when plugging my amps into a power conditioner and not directly into the wall outlet.  But it was still critically important for me to choose the right (so-called) non-power restricting power conditioner, as they are not all created equal.  Ultimately, I selected the Audioquest Niagara 3000 as my reference power conditioner, which my power amplifier is plugged directly into one of it’s high-current outlets.  I’m extremely pleased with the Audioquest Niagara 3000 power conditioner which, in the future, I’ll always plug all my amplifiers directly into such a device. Oh yeah, I also made sure I used a very high-end, quality power cable from my upgraded wall outlet, to my power conditioner.  Happy listening.