The failing is not that the employee equity math rarely works out, it's that the "industry" is so focused on equity. It often falls short as a recruiting tool (a significant number of prospective employees are clued in to the fact that it's likely to be worthless) and it's usually a poor retention tool as well (just look at startup turnover and the number of employees who don't stay with one company long enough to fully vest).
The startup value proposition today is actually quite compelling in some cases. Employees, many of them young and without significant real-world experience, can earn six-figure salaries working at companies that, without outside investment, could not sustain themselves.
Too much capital chasing too few opportunities has given many startup founders the ability to raise capital on terms that are insane. I mean, you have entrepreneurs raising million-plus convertible note seed rounds with caps that make absolutely no sense. Where does all that cheap money go? For many if not most startups, one word: salaries.
If you're being paid $120,000/year plus benefits to work on a CRUD Rails app at a startup that probably won't be around in five years, you should forget about equity. You have already won the lottery.
