I hope more people read comments like these and ask themselves: "What warrants these life suggestions? Are they justified? What would make them justified? What alternatives are there?"
There's an argument to holding on X money will let you make more money, therefore making your actual contributions larger / more valuable
You can more easily invest your second million than your first (Because you probably need that (Or at least a portion of that to live)
There's also no significant reason to start earlier (or later), unless you factor in dying as your stopping point, worthwhile causes aren't going anywhere
Edit: Not talking purely about financially giving back, but also volunteering your time.