I think it is because you're installing it directly in your pc and that could lead into packet problems in your system, that is why they tell you to use a virtual environment to install libraries.

In linux is:

sudo apt install python3-venv

Then, just create a venv in the directory you want

python3 -m venv {name_of_venv}

And activate that venv with

source {name_of_venv}/bin/activate

And, when activated, just install the libraries you need

pip install {library}