It used to be expected of older, physically slower PCs, but these days it's true even of brand new computers.
I mean, back in the day - when I first started working as a PC technician back in 1999, I had a 486DX 100mhz with 48mb of RAM using Windows 98 2nd edition, and that was faster than most of the newer PC's I've used since. Such was my expertise back then that I rigged up a live toggle switch to the jumper settings on the board so that - while the PC was running - I could overclock it to 120mhz - play my first-person shooters - and then set it back down to 100mhz again. I even managed to play Heretic and Hexen on it smoothly, and without any trouble. I even built a cooling duct over the CPU and heat sink that ran to a fan at the front of the case to improve cooling and stability, and occasionally augmented that by placing a saucer filled with ice cubes in front of the case so that chilled air would be sucked in!
But then we got newer, faster PCs - with more RAM, bigger multi-core CPUs - and much, much bigger Windows.