It’s not usually an issue, but sometimes complex permission or file structure issues can appear in non-standard installs when you try to use poorly-coded plugins or add-ons that aren’t expecting custom setups.) Installs can sometimes go wonky when it’s just one account! It’s generally simpler to install GIMP for everyone unless you don’t have admin permissions.
Next, you’ll need to decide if you want to install GIMP for everyone with an account on the computer or just for your own account.
Best to install for all users, as recommended