Early Installment Weirdness / Professional Wrestling
Prior to the rise of the National Wrestling Alliance 1948, the rival sports of pro boxing and pro wrestling were largely governed by the same athletic commission in the USA. Despite the rise of the NWA and UWA, however, a good deal of Mexican Lucha Libre is still governed by the same commission that handles boxing, though it is still a minor example since it used to be known as the wrestle y box, rather than the box y lucha libre.
Prior to 1956, not one of EMLL's anniversary shows took place in Arena México. After 1956, every last one of their anniversary shows took place there. Also, prior to 1977, there were multiple anniversary shows, rather than just one annually.
When Frontier Martial-Arts Wrestling started out, it actually lived up to its name, pitting pro wrestlers against martial artists of other styles. However, as time went on "everything should be allowed in puroresu" started to reach it's logical extreme and FMW became best known for being that promotion that indirectly coined the term "Garbage Wrestler" and was most celebrated by it's fan base for showcasing several different styles of pro wrestling.
ECW was initially an old school regional based promotion note The E originally stood for "Eastern." before it adopted garbage wrestling and a heavier, more "extreme" atmosphere.
Ring of Honor started out as a "super indie" with very open ended contracts to which only a few wrestlers were signed with the goal of simply showcasing the best in the world. This came to a fairly quick end when Ric Flair no showed an event without notice. Also, the company began as a money making vehicle for RF Video, who it broke away from after only two years. And it only did 20 something shows a year as a opposed to the 52+/one a week that would become standard when it got HD net.
Figure Four Online Weekly started out as a parody newsletter before becoming a legitimate extension of The Wrestling Observer.
Watch any wrestler work a gimmick they played before becoming famous (e.g. The Undertaker during his "Mean" Mark Callous days), or during their days as a jobber or jobber-to-the-stars before they received gimmicks in the first place, and it will feel weird watching it.