The Analysis accumulates an approximate figure on what can be cleaned.
When the cleaner is run it accumulates what could actually be cleaned at that time.
Some areas may be locked or unavailable at the time or an area has already been deleted by some other process. Some areas are protected by security programs, etc.
I had thought as much re some scanned but possibly "locked" files.
The interesting thing is when run immediately again post clean-up, either same cc session or close and restart = all clear
??
Yes, that shows how close the timing can be.
However, there can be some situations that occur every now and then when a combination of things such as OS and version and language being used etc. etc, that do show a "bug" has arisen.
If such differences keep occurring and you are only running CCleaner by itself and after browsers have had time to actually close then supply enough info for the "bug fixers" to track this down.
80 MB is an expected figure for Temp.Int. Files after a bit of browsing. Do you have a browser that cleans-up after itself based on options that have been set?