Put most simply, what stands in nearest proximity to you has enormous implications. As Jim Rohn has wisely said, “You are the average of the five people you spend the most time with.” Similarly, Tim Sanders, former Yahoo! director, said, “Your network is your net worth.”
If you genuinely want to become better, you must surround yourself with people who will hold you to a higher standard than you currently hold yourself. You want to be around people with a higher and better vantage-point than you have, so that you can quickly learn from them.
When I first started climbing I learned from someone I befriended that worked at my local gym. I was stronger than he but his technique was light years ahead of mine. As we climbed together indoors and out, I got better and eventually I was climbing stronger than he was since he brought me up to his technique level.
My climbing buddy moved away and I started climbing with a group of much stronger climbers and I was again the low man on the totem pole. However, before long I was climbing at their level and we all pushed each other on a daily basis. I've never climbed stronger (outside) than I did with that group of climbing friends.
The moral of my little story?... This article is a perfect snapshot of why, in anything, you should surround yourself with people who will raise your standards of whatever it is you're pursuing.