according to different observation i think few ways are available for abusing bitcoins transections such as Technical weakness , Greedy peoples ro dishonest people , proper management. i would like to describe above mentioned quotatin in briefly
1. technical weakness: we know its a peer to peer transection system throgh confirmed way. within a few second a dishonest person can get more money by fast clicking when submit second payment of different recipient.
2. proper management: there is so many lack of proper management of human or account holders. so many hackers want to hack system for getting money because bitcoins holder don't have any insurance like bank account holders. even government don't follow rules and regulation for virtual currency holders.
So what you think about it ?
Bitcoin is decentralized which means transactions are not under the authority of the government which allows the users to use it as they would want to. As such, improper use of Bitcoin is based on how will it be used and where will it be spent. Crimes rekated to drugs is the most common improper way of using Bitcoin.