Why do my myLot earnings update only about every 24 hours?

That could be because with the total number of messages that is being posted at a given point of time, it will be very difficult to calculate earnings. I guess they have an algorithm which will calculate the earnings based on the quality and quantity that you type and running it every time someone posts will make the website slow, I guess. More ever they are doing it perfectly every 24 hours, there is no harm in that, at least they are updating it regularly, we should appreciate that. There is nothing wrong in waiting to see our earnings every day, this also gives us anticipation on how much we are earning daily.

Might be that if they update instantly people will be more interested to view their earnings than in promoting the site.