Are pre-launch discounts truly beneficial for investors?

Visited Emaar's upcoming project near Greater Kailash II last Saturday. Builders often present 'early bird' or 'pre-launch' pricing as a significant advantage. However, my analysis suggests these initial savings sometimes don't fully offset construction risk and potential delays. I've observed instances where pre-launch investors, after factoring in extended EMIs and opportunity cost, see their effective acquisition cost align with later open-market prices. For Delhi's current market, what's the actual ROI difference people are experiencing? Is it more prudent to secure a ready-to-move property with a spot discount, or do these early offers genuinely provide superior value? Seeking insights on true pre-launch benefits versus secondary market opportunities, particularly from an investment viewpoint.