community 
Limit the amount of times shells/scripts requirements are being updated
When you execute a script for the first time, it will first create the venv and then install the requirements (if there is a requirements.txt file).
For each subsequent run, before the script runs, there is first a phase of checking for some requirements updates (pip install --update).
This step is also a blocking one, so if you have multiple setup/teardown/other scripts from the same type that should run in parallel - they will be waiting for a 'install req' to finish, which in turn causes a delay in the execution of each such script. Especially if it has multiple requirements with multiple dependencies - this process can take anything between 20 seconds to 2 minutes - and it gets multiplied by each script.
This is really not a needed behavior - packages are not being updated that frequently that we'll need to check for new update for every script execution. Once a day/week can be good enough (if there is a known issue in a specific package and you want to get a new version, you can always force it by deleting the venv or updating the script).
This idea is somewhat related to this one, which is mostly for dev purposes, but with the above idea you're covering day-to-day behavior/slowness.
