It's just like a small college engineering class. The top 3 in the class are usually scarily smart, while there are always the bottom 5 that have little clue what they are doing and failing, and then the rest would be happy to just passing the class. Same thing in the work place, there are a few extremely smart guys who you can never measure up to, and then there are a bunch of guys who never gets it no matter how long they have been in their job. No need to panic, you have your place in the company as long as you do your job.