1. You had been scammed
2. You do see your bitcoin investment had plummets
3. Your wallet get hacked
4. Irreversible transactions error or simply sent out funds in wrong wallet
This four points is what is common and attributed to the newbies as they majorly fall a victim of these dissapointment of a thing at their first approach, what tou don't know may cost you heavily because it has become an asset to someone to feast on, also this disappointment of a thing is common in bitcoin price since it's a digital currency that is volatile, we cannot accurately predict the next phase of what may turn the price of bitcoin and even some experience users fall into this same category in disappointment.