There's a difference between typos (and autocorrection, the bane of my life!) and actual bad spelling. A whole generation missed out on spelling tests at school, and hence really struggle now. I feel for them. invesment is clearly a typo and should have been picked up on reading it through, which some people don't bother to do.
I used to type medical correspondence from dictation many years ago, and was alarmed that the doctors never checked their letters, just signed them in haste before going out on visits. But then I realised they actually trusted me to get it right, so I had to!
Our Welfare State. Is it broken?