To my reading, 1 Corinthians 12:4-30 could be summed up as: "Be content with the gifts/role God has given you because in his sight all the functions of the body of Christ are of equal importance".
Why then does the chapter end with:
But earnestly desire the higher gifts. ESV
Which Paul goes on to restate at the beginning of chapter 14:
Pursue love, and earnestly desire the spiritual gifts, especially that you may prophesy ESV
Given the principle of letting scripture interpret scripture, how should we interpret chapter 12 in a way that does not let Paul contradict himself