question about bootvis

Microsoft Windows XP

I've used bootvis a number of times to optimise or examine my boot sequence.
My question is: once it has optimised my system, why doesn't the effect last
into the next bootups? I mean, I set it to optimise the system, reboot, and
I notice the effect immediately. And yet the following reboots go back to
normal, and are longer. I don't see the point in "optimising" if the effect
doesn't last.

There are other things to optimise than the base set bootvis deals with.
XP has a 'Prefetch' system that does optimisation every three days of
not only the boot files but of others used in the loading of programs.
And may adjust some of the boot set so as to have better results on your
commonly used programs, where load times are more important (you can
always go get a cup of coffee during boot)