Actually it is Troubles plural, i can think of two big ones off the top of my head…
Trouble #1. When you eventually find the perfect one they will in all likelihood choose to wait until they meet their perfect partner rather than choosing you.
Trouble #2. If you find the one who is perfect in your eyes you may very well find that living with someone who is perfect can be… somewhat of a challenge to the old ego.
It’s not easy living with someone who always does the right thing, never makes mistakes, can never be helped to do something (because they CAN actually do everything better than you) and even if they have the perfect manners to not say so, knowing that you will never be able to quite match up to their level of perfection is just a teeny bit confidence destroying, not to mention mentally exhausting.
I speak from experience.
AS i’m sure can many others. 😉