There actually haven't been that many, and double-checking against Wikipedia I forgot Parag Agrawal but Wikipedia forgot Linda Yaccarino. I divide them up into eras and power struggles:
1. Jack Dorsey. Founding era, founding engineer, forced out when Twitter was ~30 employees because he had no management experience.
2. Evan Williams. Growth era. Another founder, but one who had past experience dealing with hypergrowth, getting companies acquired, and working inside a big company.
3. Dick Costolo. Maturation era. Adult supervision, he's the professional CEO hired to manage Twitter because both of its previous CEOs were really startup people.
4. Jack Dorsey (2). Came back after gaining some political savvy and learning how to launch a boardroom coup. Founded Square in the meantime and got a bunch of experience being CEO of another company. Also famously the guy who shut down the Jan 6th insurrection by blocking the sitting U.S. president from Twitter.
5. Parag Agrawal. Caretaker; Twitter was in trouble by then and Jack Dorsey was either forced out or decided it was better to die a hero than be remembered as a villain.
6. Elon Musk. Bought Twitter in a fit of insanity.
7. Linda Yaccarino. Glass cliff. Installed as CEO so that X's eventual demise is not Elon Musk's problem.
1. Jack Dorsey. Founding era, founding engineer, forced out when Twitter was ~30 employees because he had no management experience.
2. Evan Williams. Growth era. Another founder, but one who had past experience dealing with hypergrowth, getting companies acquired, and working inside a big company.
3. Dick Costolo. Maturation era. Adult supervision, he's the professional CEO hired to manage Twitter because both of its previous CEOs were really startup people.
4. Jack Dorsey (2). Came back after gaining some political savvy and learning how to launch a boardroom coup. Founded Square in the meantime and got a bunch of experience being CEO of another company. Also famously the guy who shut down the Jan 6th insurrection by blocking the sitting U.S. president from Twitter.
5. Parag Agrawal. Caretaker; Twitter was in trouble by then and Jack Dorsey was either forced out or decided it was better to die a hero than be remembered as a villain.
6. Elon Musk. Bought Twitter in a fit of insanity.
7. Linda Yaccarino. Glass cliff. Installed as CEO so that X's eventual demise is not Elon Musk's problem.