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.
You don't know what you are saying and you can't even construct a proper spelling, have you even try sending or receiving a Bitcoin transaction before telling that someone can breach into the Blockchain?
Bitcoin is almost 9 years now and there is no record in the history of it that it was hacked before, Bitcoin exchanges is the hack-able though because it is centralized.
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 ?
Let a person own discretion be their tutor, it is 2017 now and the guide to everything in this world is on the Internet so it is the same when securing someone else's Bitcoin wallet. Governments doesn't need to follow any rules and regulations for cryptocurrency holder because there is none.