Holy cow, I wrote a book!
As we saw earlier,
the "Add or Remove Programs" control panel used several
heuristics to attempt to determine things like
program size and frequency of user.
Why did it bother doing this at all?
At the time the feature was added, disk space was not cheap
like it is today.
One of the problems users were having was running out of disk
space and not knowing what they could safely delete.
Thus was born the Disk Cleanup utility,
which attempted to guide the user through various things
that could be deleted in order to make disk space available.
In addition to cleaning up temporary files, you could also
remove programs that weren't being used.
But how do you know which programs you weren't using?
(Maybe you were using a program without realizing it because
it ran automatically.)
And how do you know how much disk space would be recovered
if you removed a program?
That's where the program size and frequency of use heuristics
By providing this information (or at least trying to),
the "Add or Remove Programs" control panel
could help users decide which programs to remove.
Of course, nowadays, with hard drives in the hundreds-of-gigabytes
range, disk space has become so cheap as to be nearly free.
The need to remove programs to make more disk space available
is largely gone,
but the feature remains as a vestigial organ.