Definitely not one and done! But I doubt you will be searching every year? Maybe once every 5 years hopefully on average. And in the sister comment I mentioned taking unpaid leave to do it, which will be paid by the next company paying you more salary. If I lived in the US where this would make a difference I'd be doing it now. However where I live there is only Google (not FAAN etc.) and they don't pay as much as in the US, so probably not worth it.