Remaining staff after uninstall

I just installed and uninstalled Capacities to see what files were left behind. In the MyUser\AppData\Local\capacities-updater directory, I noticed an installer.exe file weighing 353MB. Apparently, it decided to stay behind.

Why do such large files remain in the system after uninstalling your software, requiring me to manually check the folders to remove them?

If I want to install Capacities again, I won't know this file is here. I'll just download it from your website.

Capacities v1.58.53

Windows 10 Pro 22H2