Just frustrated by positions going on hold after the final round

In the last 3 months, I have appeared for PM interviews for three major startups. After collectively going through 12 interviews (3 of them in person) and 2 assignments - I have nothing to show for. The position just evaporates AFTER the whole process has been done. In one of the cases, HR also collected all the necessary documents like salary slips, appointment letter from current org and the likes and asked me put down my papers over a verbal commitment. Good thing I didn't do that. It's so ridiculous that these so called unicorns can't even do one little hiring correctly. And how it's even possible to initiate hiring if they don't even have the clarity on whether they want to hire or not? Idk if it's the consequence of a shitty job market or it's my luck. Just feeling extremely frustrated because there's nothing I can do about it. I clear all the interviews and do the assignments perfectly - what else I can do? HRs don't even have the guts to apprise me proactively. They'll just stall releasing of the offer letter for weeks and stop taking your calls. One fine day when they finally decide to spare some of their holy time - it's usually a one line response: Position went on a hold, will let you know. Bye. Indian job market is really the worst. Absolutely zero ethics and no value for anyone's time.