Sure I'll bite, competition is incredibly hard to attain so hard in fact that it doesn't exist in the real world.

For one I'll say that when we talk about competition should have the following elements:

No competitor has a large market share (A large marketshare would help them influence prices which they can use to drive out other competitors taking their market share) Almost no barrier to enter and exit the competition Consumers have perfect information

Now ignoring that 'competitors' will activly try to destroy perfect competitions to go for higher profits why do even consumers not want competition? Economies of Scale

In order to have perfect competition you need an 'excess' of competitors. So think 100 furniture factories when 10 could do that work, every factory needs to figure out their own logistics, sale and management, this means that the state of competition is less efficient than a state that is closer to a monopoly/duopoly/oligopoly with several larger companies, even if those companies suck.

This is also of course ignoring natural monopolies aka utilities.