Barry Allen might be the fastest man alive, or at least one of them, as his solo TV show The Flash demonstrated multiple times. But even Barry's unusual speed doesn't guarantee that the show will be able to finish every single storyline it starts. Sometimes things and matters the show focused on ended prematurely or simply ran their course. And sometimes, The Flash downright dropped them.
However, that can be considered a natural progression. After all, each new season of the show introduces a new major villain, and with it come new problems. Still, it would have been nice to see some of the dropped storylines continue a bit longer.
Wally's Involvement In The Team
When Wally first showed up in The Flash, it took him a while to find his way to the rest of his family. But they bonded in the end. Once Wally got his powers, it looked like he was on his best way to become an inseparable part of the Team Flash. And for a while, he was. Except Wally later joined the Legends and now he's doing - actually, it's unclear what he's doing. He briefly showed up on the show again but left fast and now he's flying solo.
Caitlin's And Julian's Relationship
Caitlin hasn't had the best of luck at relationships and Julian Albert hasn't changed the status quo. When Tom Felton joined the show in the third season, the fans were excited. But it eventually turned out Julian wouldn't be staying with the team forever. He formed a bond with Caitlin and wanted to help her, had a crush on her, but left eventually and the show didn't address the potential relationship again.
The Flashpoint's Consequences
One of Barry's most selfish acts was when he went back in time, saved his mom and dad, and created an alternate timeline. Barry never took the time to think about what would his actions mean for his friends and all the other people in the world.
It's understandable he wanted to save his mom but this wasn't the best way to do it. It led to Caitlin getting her powers and Cisco's brother dying. Yet the show eventually dropped the storyline and made it look like Barry's actions had no further consequences.
Lisa Doesn't Know Her Brother Is Dead
Captain Cold's sister Lisa Snart first appeared on The Flash when she tricked Cisco. She forced him to make new weapons for the Rogues. However, she also seemed to have liked Cisco and even kissed him at one point.
When her brother departed the show, so did Lisa. It's unclear what became of her, and considering that Leonard died while traveling through time, Lisa might even not have any idea her brother is dead.
Caitlin's Problems Are Gone
In the previous seasons, Caitlin struggled a lot. After she聽started to become Killer Frost, and learned that this superpowered side had always been part of her, she had trouble聽integrating with the two sides of herself. And to make matters even worse, she had health issues. Yet when Caitlin returned in recent episodes, she seemed much better and it was like all her problems just disappeared.
Ralph And Sue
Speaking of former members of the Team Flash, one who won't be coming back for sure is Ralph Dibny. Ralph's actor Hartley Sawyer was fired from the show after he had made some unsavory comments on social media. As a result, Ralph's story will most likely remain unfinished.
According to the first episode of the seventh season, he's gone into hiding with Sue Dearborn. If not Ralph, then at least Sue could come back but it's doubtful whether that will happen considering how closely connected their stories seemed to be on the show.
Jesse Quick And Wally
Jesse and Wally dated for a while but Jessie then broke up with him - and she didn't even do it in person.
The ending of the relationship came out of nowhere and it wasn't exactly in line with Jessie's character to dump Wally this way. It's unlikely her story will continue since Earth-2 was destroyed and Jesse is most likely gone, just like her dad is.
Barry's Other Romantic Relationship Besides Iris
Every fan of the comics knew that Barry and Iris were the OTP. As a result, every other romantic relationship Barry had on the show had an expiration date and the show's creators dropped the storyline sooner or later. It most notably happened with two women - Linda Park and Patty Spivot.
Linda dated Wally West in the comics but the show matched her with Barry instead. And as for Patty, she worked for the SCPD but later moved to another city. Neither of them has appeared on The Flash for quite a long time by now.
The S.T.A.R. Labs Museum
Some fans have wondered how Barry and his friends make so much money to be able to afford their standard of living. One of the possible answers could be the S.T.A.R. Labs Museum. HR Wells came with the idea in the third season. The museum does indeed open later on, but afterward, there were zero mentions of it in the upcoming seasons of the show. That's a bit unfair to the late HR considering how much thought and effort he put into it.
The New Justice League
In the crossover Crisis on Infinite Earths聽Barry and his friends as well as other superheroes form a new superhero team - quite possibly the Justice League. They even get new headquarters. And ever since then, they met there - exactly zero times. It's like the whole establishment stopped existing. It's true that Barry had his hands full, what with Iris missing and his team away, but this feels like a serious oversight.
