Team Guy is one of the most endearing ninja teams from Konoha village. While Rock Lee and Neji got plenty of screentime and popularity, no character got as disrespected as Tenten.
Naruto isn’t known for a fair representation of its female characters. Even so, it gave us gems like Tsunade, a legendary character. Tenten had all the makings of becoming an interesting character in her own right. However, she was reduced to a stock character with flashy weapons.
History of Tenten

Tenten had a dream of becoming a renowned kunoichi like Tsunade, one of the Sannin, since she was a student at the Academy, which she openly discussed with others. She was sent to Might Guy's tutelage after graduation, alongside her peers Rock Lee and Neji Hyuga. Guy made his potential trainees spar with him in order to see their commitment to succeed in their final test to become genin.
All three were successful in the end. Tenten attempted to become a medical-nin during this period of trial and error, hoping to match Tsunade's raw power and such. Tenten eventually realized her knack for fuinjutsu and developed her own fighting technique as a result of each failed attempt.
Tenten’s Personality

In the former days of the show, Tenten is shown as inherently curious and perceptive, with a personal ambition to become a great kunoichi like Tsunade. This has caused her to have strong feelings towards women, arguing that girls can be just as talented in taijutsu as boys when Neji disagreed.
Tenten isn't fond of weakness or being overly reliant on other people. Moreover, she is gentle and kind toward others, soothing her pals when they are going through a difficult moment, despite her fierceness at times.
What Went Wrong With Tenten?

Tenten is a classic failure of the "show don’t tell: mantra of writing a good story". Everything we know about her is everything we are told but never shown the full scope of.
Tenten apparently has the ability to use any weapon. She is the best weapon master of the entire Konoha, probably all 5 villages. However, we are never shown her full potential or her journey towards becoming a weapon master. As a result, when we see Tenten swinging Bashoshen at Kakuzu’s heart, we do not care.
Her ability to store weapons in her scrolls was an ability that could have been utilized in many crucial moments. However, like most women in Naruto, her actions and abilities do not ever make any significant difference to the story itself.
In Tenten Kishimoto created a character that didn’t want to be left behind. She wanted to show that girls can be just as capable as guys. However, this mentality is never explored or used in a storyline.

The only fight Tenten ever won was against her doppelganger. What was the point of creating a “can use any weapon”, “perfect marksmanship” character if she was never going to be useful in any meaningful way?
However, the most frustrating part of Tenten’s character is her arc. A character that grew up idolizing another person finds out they can never become their idol. They then have to grapple with the reality of not being able to fulfill their childhood dream and create a new path for themself. This sounds like such a compelling story in itself. However, Tenten was neither given enough importance nor screentime for Kishimoto to ever actually explore her arc in a fulfilling way. As a result, we only see a shadow of what Tenten could have been as a character.