I invest in my own training and certifications just like I did for my graduate and postgraduate degrees. There are a couple of reasons:

1. When I invest in myself I can choose what I want to learn. Often it is directly related to my job, but not always.

2. I do not want to "owe" a certain amount of employment to a company I'm working for. If I want to move on I can without strings attached.

3. I often ask for training and sometimes get it paid for, but that is never going to provide as much knowledge as I want and need.

4. It's good for a career to "save the day" when something is going terribly wrong and no one at the company has been trained in how to resolve the issue. For you Star Trek fans, that's what Mr. Scott does.

Should a company pay for job specific training? Yes, I think they should. Is that the real world? Not so much. I can growl about it or do something about it. I choose the latter - usually.