This is a serious question and I have thought about it a lot. Not a newbie question. I am unsatisfied with the common answers
- they try to sell things
- they try to scam you
- they try to do phishing
- they make you click on something malicious
Those are all obvious and reasonable motivations for sending spam email, and there is no question.
But in my experience, the vast majority of spam is none of those kinds. The vast majority I have encountered (before I decided to no even open emails any more that I don't expect) they were full of nonsense just words strung together making zero sense. And if they did offer "cheap cialis" or something there often wasn't even a link to click to actually go to a phishing site or a scam or sales site. Most spam just appears utterly pointless.
So why do spammers still flood the internet with completely pointless emails?
I have my suspicions, but I'd like to know what is known about this phenomenon. I think some motivation might be to mask higher pay-off spam with bogus so that spam filters will be overloaded and skew the system to let real threats through easier. Another possibility is that some (state actor?) just wants to suck resources out of the economy by making email almost useless.