I see what you are saying there. I myself am a really private person. But the most important thing about goals is to achieve them, and repeating them constantly to ourselves (and why not, sometimes sharing them) will keep you focused on them. It will prevent you from forgetting them or not giving them the importance they deserve. And if you share them with someone you respect, you won't want to fail them, and motivation adds up. At least that's what I think...