P.M.
Of course he's seeking attention – he's 3! (or 4! or 5! or…).
But seriously, so much is being learned about children's motivation, and so much depends on the way we encourage them. Some 'encouragement' is actually demotivating. Here's a wonderful article on the latest research – I'm sure you'll read things that will surprise you and cause you to rethink the kinds of encouragement you offer: How NOT to Talk to Kids, by Po Bronson: http://nymag.com/news/features/27840/