How is this even a question?
You're leaving because the company has broken promises with you, and right now they're... offering a bunch of promises.
"Oh, we'll totally give you a bonus later this year! Oh, we'll totally give you stock options! Oh, we'll totally sell the company soon and make you rich!"
Notice something? They're not actually doing anything. They didn't give you a raise. They didn't hand you money. They didn't actually give you stock options. All they did was promise stuff in the future. From a company that you're dissatisfied with because they've broken promises to you in the past!
That's Reason #1; Reason #2 is just a strong
- "Well, I'm leaving the company because of five solid reasons, none of which have to do with my current salary..."
- "How about we give you more money?"
... even if they followed through and actually gave you a raise, you're still going to:
- Be Bored
- Have a bad career progression
- Not be able to try anything new
- Work for leadership you're dissatisfied with
- Work for a company that breaks its promises with you
EDIT: Sorry, there's a Reason #3
"... but, this seems to be too good to be true! They're offering a life-changing amount of money in the near future!"
... which should always instinctively make you respond, "If it sounds too good to be true, it probably is!"