How brief should "brief" be?

<p>Hi! I hope I'm posting in the right forum...</p>

<p>One of my schools on the common app asks me to briefly state why I wish to attend there/why and how i came to select my major</p>

<p>My question is, how long is "brief"? Are we talking 2-3 sentences brief? Or a paragraph or two? Any insight is helpful!</p>

<p>Thank you!</p>