Trying to do too much sometimes works like an elevator. You think that you’ll make just a quick stop on a floor – only to discover that when you come back the elevator is gone and you have to wait for another to arrive. It ends up not being quick at all and you would have been better off heading directly to your original destination and finishing the first task at hand.
Think about your to-do list like an elevator and try to do all the things on one floor before heading to another. The less time you spend riding in the elevator, the more time you’ll have to actually accomplish tasks.