upgrade changes

Too many people screw up their systems that way for it to make sense. Sure, I do it that way myself, but then I know what I’m doing. A surprising lot of people using WordPress don’t, so recommending a full upgrade is more useful for them.

Also, the “changed files” concept would require people do to incremental upgrades. As it stands now, you can upgrade from any version of WordPress directly to any later version, one step. Can’t do that with only changed files.

Another problem is that some versions of WordPress move or delete older files. Some of those files, if they’re still there, may pose a security risk. So the best and safest way is still a delete and load from new version.

I guess it make sense what you are talking about.
I think that there is a solution for all the stuff we talked about.
an option that lets the system upgrade itself so people would not be confused of what to change.

thnx for your informative reply.