To not know your gift is a tragedy. To not use your gift is a travesty. The words speak of that which is defective. Paul was not saying that believers should get busy seeking spiritual gifts or getting gifts they do not have, but is saying that God has done no less for you than He has another. Every believer should realize that God has not deprived them of spiritual gifts.
Every believer is a gifted saint.
Each believer has a gift or gifts. Gifts are given to every man. Paul is wanting us to realize this great truth so that each believer will not live a defective Christian life. An important thing to realize about gifts is that each individual's gift is not primarily for ones own profit or prestige. They are for the profit of others.