What if all fighters were given 6-8 months off to relax, take the necessary time to properly heal injuries and ease back into training camp in preparation for the season
Which would be a 6-8 month stretch of shows/tournaments/superfights etc. 
That would never work, mma fighters take breaks inbetween fights, so to take even more time out of the year for an off season would make the sport itself inactive.
Also think of the number of fighters, hundreds all over the world. More then say 32 football teams etc... No way everyone would get a chance to showcase their skills 