At Amazon, it happens if your VP knows you and values you or your L7/L8 are willing to fight to keep you. If you were a TT or are on critical path for a D team/S team goal, it helps too. If you are just an average HV SDE2 on a big team, no luck.
It is very difficult to satisfy all these requirements. Easier to interview and jump the ship. Simply too many stars should align. It is easier to be TT sde2 than TT sde3. Though, sde3 has a better chance for visibility at L7 / L8 levels.
So do the math... Let's say stock goes to $50 and you are able to vest and sell all. 15k into 50 is $750k If you sell short term, company will remove the ones for taxes..at say highest marginal rate of 40% which is most bonuses get taxed at so you are left with $500k. If stock is at a different price you can do the math.. But half a million which is not bad for a years worth of work
Lyft Inc. is preparing to list its shares on Nasdaq around the end of March, according to people familiar with the matter, as the ride-sharing firm’s hotly anticipated plan to join the public markets comes into focus.