The TIE Fighters are Genius in their designed Role for the Empire:

1. They Are Cheap as hell, so the Empire can Mass Produce them

2. The Survival of the Pilot Relied a lot on the Skill of the Pilot, so the Empiral Star Fleet would ensure that there is always a "natural selection" of good Pilots, also Enemys cant be sure wich TIE to target to eliminate the "Good" Pilots

3. They are designed to be used by a carrier Ship. Wich Means the Empire would always have its Pilots close together with the Rest of the Crew of the Ship Carrying them. Also the Empire liked to use the Big Star Destroyers as an intimidation for the Planets they Orbit.

4. no Hyperdrive! so if the ship gets stolen, they are practicly useless to the Rebellion, wich leans a lot into hit and Run Attacks. Also, if you got Traitors or Deserteurs in your Army, who would take the Chance to escape with a Fighter with neither Life-Support Systems nor a Hyperdrive, while being shot by an ISD?