You're doing it wrong (clip).There, I said it. Deal with it. Get over it and catch some fish.
You're fishing too close to the access.
You're learning to cast while learning to fish.
You're too concerned with "pretty casting".
You're trying to teach your spouse/significant other to fly fish instead of gifting them a lesson.
You're spending too much money on gear and not enough on fishing.
You're not spending enough money on gear.
You're stuck on the same tired methodology and won't experiment.
You don't take enough pictures.
You don't cover enough water.
You don't cover water thoroughly enough.
You're afraid of the woods.
You're afraid of the animals.
You're afraid of the dark.
You're afraid to get into fly tying.
You won't hire a guide.
You won't take a class.
You don't change your flies often enough.
You haven't tried streamers.
You don't fish big enough streamers.
You don't plan well enough.
You haven't tried a new river.
You won't fish for new species.
You haven't tried it in a new province or state.
You haven't taken a kid fishing.
You complain about the DNR instead of pitching in and helping.
You don't get involved.
You've forgotten that fishing is supposed to be fun and not an extension of the petty and competitive society we live in.
You're not fishing right now.