Instead, The Flash got its very own standalone pilot before going into full swing as a spinoff series.
This all may seem like history now, but The Flash was originally supposed to have a “backdoor pilot” near the end of Arrow Season 2 after introducing Grant Gustin’s Barry Allen earlier in the season.
According to a 2013 report from Deadline, the decision was made after CW executives saw cuts of the two Arrow episodes in which Barry Allen/The Flash was introduced (Episodes 8 and 9), and were so impressed that they decided to give the show’s creators the chance to work with the characters and storylines more before jumping into production.