File has been changed, but its "date modified" is the same. How is that possible?

Here is a test file test.applescript:

display dialog "foo" buttons {"OK"} cancel button 1 default button 1

At 4:05 PM I compiled it to test.app:

osacompile -o test.app test.applescript

At 4:07 PM I edited test.applescript by replacing foo with bar, and then compiled it again, overwriting the existing test.app file. (It was overwritten successfully. If I run it, the dialog shows me "bar", not "foo".)

display dialog "bar" buttons {"OK"} cancel button 1 default button 1

osacompile -o test.app test.applescript

But nevertheless the date modified value of test.app is still 4:05 PM. Why is that? How is that possible? Output of stat -x:

File: "test.app"
  Size: 96           FileType: Directory
  Mode: (0755/drwxr-xr-x)         Uid: (  501/    john)  Gid: (   20/   staff)
Device: 1,17   Inode: 79429067    Links: 3
Access: Sun Mar 23 16:05:52 2025
Modify: Sun Mar 23 16:05:52 2025
Change: Sun Mar 23 17:20:48 2025
 Birth: Sun Mar 23 16:05:52 2025