Why shouldn’t we use words such as ‘here’ and ‘this’ in textlinks?

Over the years of surfing on the web I have found numerous examples of people saying that you shouldn't use the word "here" in a textlink etc. Personally I like the idea of using the word, because it is so straightforward for your visitors to know where to click.

The only reason that I can truly think of is for SEO purposes. The word here doesn't have much value as a keyword as such.

I would like to know some other opinions on why we should/shouldn't use word like "this" and "here" in a textlink.