In the first course, I have talked about the best sessions to trade and we have discovered that there are times during the day, when the volatility is very low and the market seems to be quiet.
During these periods (essentially during the Sydney session), if you are trading on a low time frame, such as 15M or lower, you will probably find a lot of dojis.

This EUR/USD 5M chart is showing a lot of dojis during the Sydney session.
When the volatility is low, the chances of opening and closing at the same price increase.
This usually reflects a market where key players are not around to trade, it doesn't indicate any major reversal in thinking about the market.