Use it or lose it. Without a doubt, you have to grow in all skills area. Now, with today's technology, it is a lot of easier to get up to speed. But I see it in all walks of life. If you're out of work for a while, or when kids return to school after the summer break, it can be slow going. The speed of technological growth now requires us to upgrade our skills yearly. Within a few years, it might be every 6 months.