Every Legend in Apex Legends has three major types of abilities: Passive, Tactical, and Ultimate. However, some Legends also have one additional ability called a Perk. Perks have been in the game since launch and were initially put in place to even out how Legends play with their different hitbox sizes.
Apex Legends is a battle royale, but it is also a hero shooter. Having different-sized Legends brought personality to them and the game. That said, this has made balancing the Legends a development nightmare. Perks were never there to be a feature; they were there to be a fix. Legends with small hitboxes would get Low Profile, a perk that made them even harder to hit, but caused them to take 5% more damage when they were hit. Legends with large hitboxes would get Fortified, a perk that prevent 15% of incoming damage and prevent being slowed by bullets.
There is some argument over whether the Survey Beacon recon ability is a Perk or an additional passive, but for the sake of the article, we will not be including it.
In Season 8, Low Profile was removed from Pathfinder after rebalancing him. With Season 9: Legacy, Low Profile has been removed from the game entirely. The developers have balanced Wraith, Wattson, and Lifeline further to the point they feel it is no longer needed. Their hope is to eventually get Gibraltar and Caustic to that point as well, and remove all instances of Fortified, though that will be further down the line.
All and all, Perks were never really meant to be in the game. They were a bandage for a bullet hole in the game design, and the team just feels like they don’t belong. The day they can remove Fortified from Gibraltar and Caustic will be the day Respawn will finally have achieved their Legend hitbox balance goals.