According to Ipsos Messaging Anti-Abuse Working Group (MAAWG), nearly half of a recently surveyed audience opened junk e-mail intentionally, in spite of the fact that many of them(about 44%) consider that they have the basic knowledge on online security. They claimed, that the reasons of opening these kind of messages are complaining to the sender, unsubscribing, interesting in the offered products and services or just curiosity of what is going to happen.

The results of the survey show that, the main responsible group of people isn’t that of the less-internet-experienced aged. People under 35 years old, seems to be these that engage in risky e-mail behavior. Ultimately, this careless way of dealing incoming e-mail, encourage spammers to keep doing their job.
References:
Cnet
Ars technica
