Whenever you buy a stock at market price, Zerodha charges a little more than the current market price.
Similarly, you can never sell a stock at market price. Always you get an amount less than the current market price.
The difference is a hidden commission taken by Zerodha. Though they say it’s free, you will lose a huge amount due to this timing difference.
I was a big fan of Zerodha until I discovered this. I switched over to another broker.