I never understood why these people don't hire an english speaking person for like, $100, to proofread some email templates for them and make corrections. They could probably scam like several % more people successfully and easily make back whatever they pay this one, single person. Not that I want them to be more successful, but it seems like, common sense...
According to one researcher, it's because the scammers only want to catch the attention of people stupid and gullible enough to fall for their scam. The bad grammar scares away the people who are just about dumb enough to believe, but not dumb enough to just hand over their passwords and credit card numbers.
Have a read of "Nigerian scam emails 'deliberately implausible'"
But it's always good to remind new players.. never ever ever ever click on these links.