I'm a co-creator of Alexa. Writing a 6-page memo helped me decide to quit Amazon and launch my own AI startup.

William Tunstall-Pedoe is the founder and CEO of UnlikelyAI.

Courtesy of William Tunstall-Pedoe

• William Tunstall-Pedoe founded True Knowledge, later Evi, which Amazon acquired to build Alexa.
• He left Amazon in 2016 after almost four years at the tech giant to re-enter the startup world.
• He used a six-page memo to decide whether he should leave Amazon.

This as-told-to essay is based on a conversation with William Tunstall-Pedoe, 56, a founder and CEO. Amazon's...