Most of the time, stock markets seem "random"; they rise one day and fall the next, and often their condition changes between different trading sessions on the same day. Sometimes this happens due to positive information that led to a market rise or negative information that led to a decline.

However, market declines and rises often occur due to the behaviors of speculators. When the market drops to a certain extent, some traders see it as an opportunity to buy, thus entering the market and bringing some movement and upward momentum back to it. The opposite happens during a rise, where selling occurs to reap profits.