I think the most effective way to hire is to do your best without giving into to grueling whiteboard interviews, and take a chance on someone who seems smart. But also fire the person quickly if it seems like they won't be a good fit. After spending years interviewing people, this is the best conclusion I've come up with, because nothing else works as conclusively. Yes, it's brutal, and a bit ruthless, but effective. Whiteboard interview questions are a terrible measure of whether someone will be able to contribute. Same goes for the other types of interview questions.
Of course, you need to give the person a chance to ramp up, etc, but if they can't be a contributing team member in 2 months, then it's better to give them 1-2 month's severance and get rid of them. I know one late-stage startup in the city that is using this technique, and I believe (not sure) that both Amazon and Netflix use this technique as well. It sucks, and kind of creates a bit of a harsh environment, but it's a fast way to build out your team, and probably has the same success rate as any other interview method, if not better because you cull your bad performers quickly.
Of course, you need to give the person a chance to ramp up, etc, but if they can't be a contributing team member in 2 months, then it's better to give them 1-2 month's severance and get rid of them. I know one late-stage startup in the city that is using this technique, and I believe (not sure) that both Amazon and Netflix use this technique as well. It sucks, and kind of creates a bit of a harsh environment, but it's a fast way to build out your team, and probably has the same success rate as any other interview method, if not better because you cull your bad performers quickly.