Also, an upgrade rather than a clean install could also show potential issues that were hidden until the upgrade to Windows 11.
But then I would say John would be correct on the hardware piece. If it had Windows 10 before then you are probably looking at a 3-4 year minimum old machine so there may be some difference if you are doing an in-place upgrade vs. clean install. Drivers could be a factor also (i.e. older hardware may not be supported with Windows 11 drivers).