If you’ve recently browsed through your installed apps list in Windows 11 settings, you might have done a double-take. That simple video player you installed is apparently taking up 2GB, or a basic text editor is hogging 500MB.
Messaging and streaming apps (like WhatsApp, Spotify, or Slack) store photos, videos, and music locally so they don't have to re-download them.
Windows often keeps "rollback" data and installer files in the WinSxS or Installer folders so you can uninstall updates if they break something. These can grow to tens of gigabytes.
The single biggest reason for the size increase is how modern software is built.
Which are showing the largest sizes (e.g., Games, Adobe, System apps)? How much total free space you currently have left?