We have team leads at our company that hate to train or take on new people that don't meet a minimum standard, or can't work semi-autonomously right away. Fools they are, and here's why:
1. I frequently find myself overwhelmed with meetings, little tasks by the bushel, and stuff I just don't plain want to do. Send me the inexperienced guy, and I'll spend a day or a week or a month showing them the bare basics of what they need to know to get "close enough" on the job (like how to take notes/report status in a redundant, low-level meeting or do do a repetetive but necessary task or report). *poof* All the thankless little tasks go away, taken over by someone else, and I get credit for both training the new guys AND for doing work more appropriate for my experience level.
2. If the new guy's competent, he finds a way to make these tasks better -- for him/her. It's a critical thought exercise. Meet enough people, show you are competent/network. At the same time I'm showing the new guy (and sundry others) that I have faith in them. Most times that's paid off as they've moved to other projects/offices as I now have a trust relationship.
3. I train 'em my way. Makes my job easier. If they show competence in technical work, I work with them and bring them up my way, and it makes it easier to work together. If the have project management skills, I try to find them opportunities along those lines. Hate to lose a technical expert, but a technically competent manager is gold at our company. A technically competent manager I've worked well with is completely priceless to me.
4. If they don't work out, they're gone. I'm willing to train folks, but sometimes it doesn't work out, and it's to the company's benefit to identify general incompetence as quick as possible.
Not everyone thinks like I do, that's cool. I'm just willing to make the time to train the next generation 'cause I see some (possibly self-serving) benefit.