Invest with Lighthouse-in-the-sea!

One of my friends doesn't trade in Nifty.

He "invests" in nifty.

I asked him the reason.

"Investing in Nifty is like investing in all 50 bluechip stocks in the index!", he said.

"and it is safe since my eggs are in 50 baskets!"

"And why do you call it investing instead of trading?", I asked.

"Because I stay invested in it for 3-8 months and not get in or out like a trader!", he shared.

"It gives me much more returns (500-800 points) than a trader with almost no stress!"

"But in that case, you might be falling whenever Nifty falls!", I retorted.

"Nifty rarely falls after I make my investment." he said.

"How come?" I asked curiously.

"I always invest when I see a lighthouse-in-the-sea! And there is always a lighthouse after every 3-8 miles (months)!!", he said with a mysterious smile.

Then he showed me what he meant by "the lighthouse-in-the-sea".

He was talking about William%R on the 5 year chart of nifty (reproduced below)