On the other hand the attacker may actually have incentive to follow through and hold up their end so as to build a reputation. Making their next victims more likely to just pay.
Somewhere I read that some ransomware had excellent "customer" service for helping you transfer over the payment and promptly restore your files.
This stat includes everyone, some of them may not research what hit them. One of my clients decrypted his database twice, after seeing on the internet that they actually send a decryption key.
