I've almost for 3 years already been planning to leave my current job (even got 3 offers during that time, though only 2 were plausible as the 3rd was from the very big well known SV company and for some reason they knowingly offered less than i was making at the time (why were to bother at all?)). In my experience the best a tech person can do for their professional growth, incl. enriching experience, exposure to more tech as well as higher salary is to change jobs. I just become too comfortable at my current place and it doesn't do good for me - hitting 5 years soon here - so current plans is by the very beginning of the next year (just to make sure to get this year bonus :)

It's from a poll of employees on a job / recruitment site. I'm surprised it's only 88%.

I don't know...what's going to keep them on?

Solving interesting problems? Having a meaningful impact on business decisions? Getting paid well? Being treated and respected by their employers? Learning new things?

Frankly, there's not a lot encouraging people to stay.

Why not? There's plenty of turnover in tech jobs, and talented developers mostly find themselves in a seller's job market.