It depends what you are trying to achieve in your trout fishing. I have got to a stage where the challenge is for me to tie and present a fly that imitates what the trout I am trying to catch is eating. I need to deceive the fish that my fly is food and not just to provoke an aggressive reaction. Others will have a different view and that's fine provided it's legal.

For me a fly is a fly when it looks like something that trout eat, is presented to the trout in the correct place (surface or sub surface) and moved at the natural speed for whatever it is imitating, whether that be dead drift or with some movement.

It can be anything from a tiny midge or nymph to a roach fry depending on what the trout are feeding on or regard as food.

If the fly is not used in the above scenario then it is a lure. A damselfly nymph fished in December in fast pulls is a lure not a fly.

By the way I have used Waggies for fry feeding trout and very good they were too.

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“There is no more lovely country than Monmouthshire in early spring. Nowhere do the larks sing quite so passionately, as if somehow inspired by the Welsh themselves. There is a blackbird on every thorn and a cock chaffinch, a twink as they call him there, on every bush...... It moved me profoundly. I had been spared to see another spring, and I thank God for it.”

Oliver Kite
“A Spring Day on the Usk”
A Fisherman’s Diary