Meaning of "Last Modified" date on files (installed from outside the AppStore)?

I installed the MySQLWorkbench app, but had to get it from outside the official App Store. I am using MacOS Catalina (10.15.5). So, I had to override the "warning" from Catalina, using the root password, that said to not install apps gotten from outside the app store. The MySQLWorkbench installed fine and works great.

However, I noticed the metadata on the MySQLWorkbench executable file says it was "*last modified" on April 1st, 2020. And, today, the download / install date is July 11, 2020.

So, that's weird, right? I'm just assuming the workbench was built on April 1st. ok. But, I'd still expect the file metadata to say the last modified date, for me on my file system, is today. The day I downloaded and installed it, right? I've not installed from the app store in months, but the date metadata looks as I'd expect on the apps from the app store. The date I downloaded them is their "last modified date".

I'm baffled. The April 1st date can't be correct, right?

note: I did have an earlier MySQLWorkbench that was not compatible with Catalina, and it had to be uninstalled (by dragging into the Trash) today, and replaced. But that trashed MySqlClient was installed 1 year ago, definitely not this April.

Anyway, my database and workbench are all good. But, that date metadata on the workbench executable, and the fact I got it from outside the App Store have me confused.

Solution 1:

If you copy a file from one folder to another, that does not update the creation or modification dates. Nor does making a copy in the same folder. Try it!

The same is true for 'copying' a file from a remote location, such as a network drive or downloading from the internet.

The modification date is only changed if the contents of the file are modified.

It is arguably more useful to know that 'this is a copy of the file that was created on Tuesday, and modified on Wednesday', rather than 'this is a brand new file that was made on Thursday', just because you moved it or duplicated it.

This way, you know that the file's contents are the same as other copies in other locations.