Sorry, I think there's some confusion about the usage of the word senior there, I meant senior in terms of skill level, not in terms of age. Age shouldn't be a factor at all, it doesn't matter if you're a fresh college graduate or a 60 year old so long as you have the skills to do the job. What you don't want to do is take a highly skilled worker and then hire them into a low skill position, they'll get bored/frustrated, assuming they even accept the position in the first place because presumably you're paying market rates so you'll be massively under paying them in that position.