I've worked indirectly with two 10x developers - sequentially. They worked fast and late into the night. They added every feature the product management asked

I've worked indirectly with two 10x developers - sequentially. They worked fast and late into the night. They added every feature the product management asked for and more. When the product management team rotated and the new PMs added more feature requests, they obliged whether the feature was really necessary or not and even if the other devs had pushed back on the feature. They also handled all uptime issues no matter what hour of the day. The rest of the team tried to help out but by that time the code base was too complex for 1x developers to support. Then after a few years with the company, they each ended up getting tired of doing all the leg work and moved on and the remaining team members figured out the bare minimum to kick the server when needed and promptly started on version 2.0 at a 1x pace with only the core features and more bus factor built in. That said I do think 10x devs have a sweet spot in a startup thats still trying to find product market fit and overthinking/over documenting can mean the startup never gets off the ground.