If you get down mid inhibitor...
...or any inhibitor. Go to a different lane next push. I keep losing games because we get mid inhib. Then everyone... just stands mid. What exactly are you going to do? They will just camp under their godly powerful dual nexus turrets and clear waves. You cannot engage on them there and you aren't accomplishing anything. Put pressure elsewhere. Mid is done, take another lane, dragon, baron, ANYTHING! Camping in the lane you already 'won' is pointless. Unless you have such a massive team fighting advantage that you can suffer losing two people to the Nexus turrets alone.