Should a site be in maintenance mode when running the Drush Up command?

Question

I'm not asking if I can update my website with Drush. I'm not asking if Drush can make it in maintenance mode.

My question is ... if I'm using the command drush up to update my Drupal core or a module is the best practice to put my website on maintenance mode or does not matter?

In the past, I update all my modules without putting my website in maintenance mode, and so far I have not any problems, but I'm looking for the best practice.

BTW, I already test my Drupal core update in a Dev environment, and everything is working fine.