Does a short courtship before marriage automatically count against the relationship's genuineness?

No — a short courtship before marriage does not automatically count against a relationship's genuineness. Some genuine relationships do move quickly, for all kinds of legitimate reasons, and IRCC applies the same underlying test to every relationship regardless of how long the couple knew each other before deciding to marry.

What a short courtship can do is prompt a closer look at the couple's broader evidence, simply because there is a shorter "before the marriage" history to draw on compared to a couple who dated for years first. That makes it especially useful to focus on documenting what has happened since the marriage — ongoing communication, time spent together, how life decisions have been made jointly, and how the couple's families and social circles have come to know the relationship. This after-the-wedding evidence can do a lot to show that whatever brought the couple together quickly has developed into a real, continuing relationship, not just a marriage on paper. There is no need to apologize for or over-explain a quick courtship in an application — the more productive approach is simply building a thorough, honest evidence file covering the relationship as it stands today. If you are unsure what to emphasize given your specific timeline, an immigration lawyer can help you plan the strongest presentation of your evidence.