Don't approach it as a performance review as there are a lot of people who take some time to get up to speed. If the quality of work is good, then it can be a c

Don't approach it as a performance review as there are a lot of people who take some time to get up to speed. If the quality of work is good, then it can be a casual discussion over a coffee on challenges they might be facing and the sort of productivity targets you would like them to meet within X period of time. In that context you could ask again if there are any issues they have or if there are any challenges they face that might make this difficult etc. This way you can get your message through without it becoming confrontational or the other person getting overly defensive.