It is an issue if there are VC's involved. One of the startups I co-founded and owned 25% on at outset ended up with a whopping 1% of the proceeds of the exit. I'm not bitter - in this case the exit recovered maybe 30% of the cash the VC's injected, after about 8 years - and so the dilution was understandable. But unless you bootstrap, you will increasingly be working to also enrich others, after VC's, options to other employees etc..

Exceedingly few VC-funded businesses end up with founders holding on to massive stakes all the way through to an acquisition or IPO. That is the tradeoff you make whenever you take VC money: You hope you accelerate your growth enough to more than offset the piece you give away. That is also why it is often more financially attractive for regular employees to join a VC funded startup: the growth rates are often similarly faster (but you often fail faster too, and more spectacularly; though failing faster is not necessarily a bad thing if you're first going to fail)

They were my own :-)