Panic selling is one of the main reason which contributes to the drop in the market value of bitcoins as most of the new investors do panic selling when they find that the price is dropping and they won't have much idea that they are contributing for the fall in the market value.It is a normal tendency of most of the investors to sell off their coins when they find them at high end profit rarely few hold on with their coins rest try to cash them out so that they can enjoy the benefits.