How Important Is Ventilation And Air Circulation?

This is more for a friend of mine who doesn't believe me about how important it is ..........So how important is it

need new air coming in and used air coming out or else the plants won't grow. Plus temperature rises with no ventilation/circulation

do you like sitting in a pool of your own waste?
thats how plants feel with no ventilation.

Choke said friend out and then when they wake up ask them how important "ventilation " is...they will have their answer relating to pot too!

https://www.rollitup.org/subcools-old-school-organics/50791-venting-grow-room-efficiency-get.html

Everything you need to know.

Thanks everyone point made