"Lose" has many different meanings. I suspect in this case, it is the opposite of "win," as in what happens in sports: one team wins, the other team loses. The "competition" could be the other team, or this could be a business metaphor, and the "competition" would be a rival business. You did not provide any context for the phrase, so that is the best I can do.
Thanks a lot. Actually, I did not understand the usage of "to" to say "to the competition". [I have never come across the usage of "to" with "competition" as noun] Is it the same as in the competition? Many thanks.