Long-running TV shows pack in plenty of subplots into each season. It's thus understandable when some details get forgotten by the writing team. At times, the shedding of a storyline tends to be a deliberate choice to allow the writing team to focus on more interesting angles and fresh ideas.
How I Met Your Mother was close to perfect but its handling of particular storylines was frowned upon by viewers. Perhaps the most frustrating thing was the less-than-impressive character development of Tracy aka The Mother. Other than that, the sitcom dropped a couple of oranges along the alley too.
Ellie's Mother
According to events depicted in the Season 9 episode "Last Forever - Part Two," Barney's daughter Ellie was born in 2020. Barney got a woman pregnant during what he described as his "Perfect Month." In the month, he managed to hook up with 31 women. However, the 31st woman got pregnant with his baby.
Sadly, the show never revealed who Ellie's mother was. Viewers never learn how Barney met Ellie's mother either. The only thing that came out of the story was Barney having someone he could call family.
Robin's Friends Disappeared
When Barney used the effective "Have you met Ted?" line to introduce Ted to Robin, her friends were present at the bar too. They kept pressuring her to come back to the table and stop talking to Ted.
Luckily for Ted, he managed to form a connection with Robin during their brief conversation. Interestingly, Robin's friends remained mysteries for the remainder of the series. She was only seen with them two more times. So, what happened to them? Did she drop them all in order to be with the gang? Logically, no one would drop all their friends just like that.
Tracy's Illness
Future Ted revealed that Tracy aka The Mother died of an illness in 2024. However, this was never explained in detail, What kind of illness did she have exactly?
Instead, the plot quickly moved back to the Ted and Robin romance. As the titular character, Tracy deserved to be treated a little bit better. The suspense leading up to her appearance was so intense only for her to be killed off unceremoniously. Perhaps a happily-ever-after story with Ted would have been better.
The Threeway Plan
In the first season, Ted had a one-night stand with a woman named Trudy after they exchanged numbers in the ladies' room. She then left his apartment by climbing down the fire escape. In Season 3, Ted bumped into her again.
While talking to Trudy, her college pal Rachel showed up. The two began reminiscing while voicing their attraction to Ted at the same time. They then proposed the idea of having a three-way with him. Ted was reluctant because he didn't want to earn Barney's Threeway Belt. He then seemed to reconsider again. Whether or not he did it remained a mystery.
The Mystery Of The Cockamouse
At one point in the series, Lily and Marshall saw a strange creature as they walked into their apartment. Lily insisted it was a cockroach while Marshall insisted it was a mouse. A cockroach and a mouse vary greatly in size, so, that creates a problem. They attempted to kill it using bug spray but that didn't work.
They also hit it with a phonebook, but it didn't die either. Scared, they rushed out to tell the rest of the gang about it. They called it the "cockamouse." Later on, Marshall trapped it and took it to the Columbia Biology Department. When he arrived, he no longer had it. The "cockamouse" was mentioned in several other episodes but it was never shown. What was it?
Bernice And Ted's Agreement
Bernice was supposed to sing at Ted's wedding. He probably forgot about her, and so did the writers. Ted met the elderly lady while he waited to board a train to New York at The Farhampton Train Station.
Their meeting happened after Barney and Robin's wedding. After discussing the wedding, Ted promised to hire Bernice on his big day. That never happened. So, why exactly did Ted reconsider? Bernice was spotted again at the penultimate episode of the series but the wedding gig was never discussed again.
Ted's Love Solutions Match
In Season 1's "Matchmaker," Marshall, Lily, and Barney persuaded Ted to sign up for a matchmaking service named Love Solutions so that he could find his soulmate. The service found that he had zero chances of finding a soulmate. The closest match he had was already engaged.
A few episodes later, Ted received another call from the service, telling him they had found the perfect woman for him. A date was set but Ted postponed it in order to fix a tire on Marshall's car. Did Ted finally decide to go on the date? Given the challenges he had with Robin, he must have at least considered it.
Robin's Bullfighting Career
In Season 7's "Symphony of Illumination," Future Ted explained that Robin became a world-famous journalist, a rich businesswoman, a globe-trotter and, a bullfighter. Bullfighter?
The show never really explains why Robin chose such a dangerous career. What influenced her to pursue bullfighting? There is a huge contrast between journalism and bullfighting? Given how skilled and successful she was, why would she need to take on such a risky career? Was it just for thrills?
Tracy Left Mid-Reception
Ted met Tracy when he was out in the rain after leaving the wedding reception early. But Tracy's early departure doesn't make sense. Was she attending to an emergency? Her band (the SuperFreakonomics) was playing at the wedding, hence it wouldn't have been responsible for leaving the reception early.
The wedding was the only major gig that the band had gotten, hence it must have meant a lot to Tracy. It isn't known what happened to the band after Tracy's death either.
Barney's Gary Blauman Tale
Gary Blauman worked at GNB's legal department. He was also close to Marshall during his internship. Barney once told a story of how he saw Blauman being yelled at by his boss Bilson. Blauman couldn't take it so he decided to quit because he had a Plan B. He had gotten rich from an IPO when his cousin's website company went public.
While quitting, Blauman even tried to pee on the conference table. Sadly, his cousin's company failed and Blauman was forced to become a janitor. However, Blauman could still be seen at the office in future episodes, and not as a janitor. The show never explored his character again or explained how he came back.