Software's different because you can hire-fast & fire-fast. Unless you have broken processes and incompetent people surrounding the new hire, you can easily determine if they're good enough. Hack, it's even worth it to hire 2 devs for everyone you need and fire the worst performing one in a few months (flip a coin if they're pretty equal and can't afford them both).
Easier to get fired, easier to get hired. Churn and less from your employer giving a f about your career development. Every industry has its patterns.
Actually, imo the worst thing you can do as a software tech-lead is to structure your processes and projects so that hire-fast-fire-fast is no longer viable, do things so that your software is more like hardware - this is a sure way to inevitably kill the company/department you work for while "doing good work"...