According to Austen in "On Making an Agreeable Marriage," what is the most important reason for marrying someone?

According to Austen in "On Making an Agreeable Marriage", the most important reason for marrying someone is true love. As evident by her words, " Anything is to be preferred or endured rather than marrying without affection.", she deemed that love is what is essential when two people are betrothed to each other instead of mere business relations or lustful desires.