For a while yes, though it's not unheard of for a plant to puncture through the bottom of the pot and produce an extensive root system outside of the container, in the ground.

Yes, I put a pot of Lemon Balm down where intended to plant it, then forgot (oops). It's roots have escaped out of the bottom so now it has to stay there! It solved the problem of the chickens scratching up though! I also had a Passion flower that rooted through the pot and sprouted beautifully after I had removed the pot with the rest of the plant in! Aren't plants wonderful!