Some beginners on Windows think that python-3.8.3-amd64.exe, for instance, is for running python-3.8.3, leading to repeated and now tiresome questions on python-list and probably elsewhere.  The latest example is "repair modify uninstall" with the core complaint that "after downloading and trying to launch it keeps saying repair modify uninstall".  (Actually, 'modify' comes first.)

In response, Grant Edwards suggested adding run instructions to the initial screen and asked a "Is the file name not clear that it's an installer?"

For the naive, the answer, as is traditional, is 'no'. How about adding 'setup' or 'install', as I have seen occasionally.
  python-3.8.3-amd64-setup.exe

The initial screen is different according to whether an installed binary is absent or present.  For the latter, add something like

Python 3.8.3 {n} bit is installed for {who}.
To run it, {directions}
To change it, click one of the buttons below.

An optional add-on would be a button to open the doc page on using python on Windows.

(I an not suggesting a button to actually run python.exe from the installer.  Users should really learn how to start it properly according to platform and python-specific conventions and their particular needs.)

Does the final screen after installation say anything about running the new install?  (I cannot remember.)

Ned: I don't think that this issue afficts Mac newbies.  Perhaps python-xyz.pkg is more clearly not for running.  But something you might watch for.