Comment 1 for bug 1393389

pip install -U -r requirements.txt in general will only check all package having the latest version, it should not take that long. Can you double check?
In some case we update the code the requirement is also need to update. It is better to fix package version conflict early than some weird thing happens.
I do not think giving customer option to select y/n update package is better because if they ignore update package, we have less confident everything will work.