Why Can't Spammers Write a Coherent Email?

Looking at today's daily dose of spam, I was struck by a question:  why can't spammers write coherently?  This piece is about typical:

I have a good information to share with you.
A while ago,a trading company attractive to me,
the price is very competitive advantage, so I bought some products.
It is very exciting,very pleased when I got and saw my goods.
I think you can go to see: [REDACTED]
you'll save more money in there. e--.

I assume that spam filters have something to do with it, but it ought to be possible to write a better email than that.  So why don't they?

I have two working theories:

1) Spammers use low-wage foreign labor who don't speak English particularly well

2) Many Americans are used to getting real emails that look like this; something correctly punctuated, spelled, and grammaticized would look obviously fake.

Other thoughts?