A SIP is not a way to buy low on purpose. It buys on a calendar, not on a chart. The averaging only helps you when the calendar happens to walk you through a dip. It is a discipline, not a forecast.

If you already hold the lump sum, time in the market usually wins. Cash waiting to be deployed is cash not compounding. Across history, all-in beat staggering it in roughly two windows out of three.

Staggering is regret insurance, not a return engine. You trade a little expected return for a smaller chance of putting the whole amount in at the top. Worth it only if that regret is the thing that would make you sell.