Who is behind crimeware? What is their objective?

To trace the evolution of threats we have to look at the evolution of their creators. These have gone from being merely curious and looking for notoriety to looking for personal financial returns and/or forming part of a complex network of business, national or political interests.
At the same time, the level knowledge has been increasing, and tools or techniques that were yesterday only in the hands of experts, today are available to those starting out in the 'profession', thereby increasing the general skill levels of all of them.