[viscanti]

It certainly helps to already have X skill. There may be some positions where that's a non-negotiable requirement. For most, you only need to show some experience with something related to X skill, and a willingness to learn quickly.

The barrier to entry for programming is very low. Anyone can get started and build things. They can put their code up on github and start displaying what they've learned. They need to keep learning and challenging themselves though.

The problem is that there isn't a lot of demand for "smart" or "talented" people who can't contribute quickly. Someone who writes bad code and adds bugs to production software is a drag on everyone else's productivity. In most companies there just isn't the time or resources necessary to teach basic programming skills.

You probably don't need to know skill X to land a job, but you need to show that you can learn it quickly. If you can learn it quickly, then start learning it on your own. Most companies in SF don't care how old you are, they care that you can be productive quickly.

[apaitch]

It's totally understandable for a 10-man startup to not want to take in a relative newbie and have him/her drag down the team's productivity when they've got to ship in a month. However, for bigger companies (not necessarily giants like Google either) it may well be worth it to invest in a number of somewhat less experienced employees and grow them internally. The only problem, I suppose, would be selecting the right people.

[ericd]

A large percentage of "the right people" will have already invested in learning programming and the innumerable related skills, because that's what they're interested in and have been interested in for a long time. Thus, being a bit older without much experience is a bad signal from a company's perspective. But if you learn aggressively on your own, it can be overcome. Don't expect to learn all the random skills on a company's dime, though - the salaries are too high to justify that.