Stokes, I'll throw my 2 cents in here for what it's worth...
This year I've come to realize that we don't always "miss fish" when we lift on a strike and hook nothing. I firmly believe that many of the fish we "miss" may have actually missed our flies instead! Some of these fish are bumping the fly with their noses or nipping at it, and good luck with ever hooking that when it happens. Around here, I have lots of small to medium sized rainbows that quite often leap clear of the water when hitting a fly, and at least half the time they miss it entirely. Of course, at other times we just sting them and feel a bit of weight before they're gone. But I have come to stop blaming myself for every time a fish rises and I come up with nothing on my line.
Just look at where in the mouth you hook various fish. Most are gonna be in the lips or jaws, sometimes just barely so, with occasional fish losing the hook once they are safely in the net and others just popping free before we can get the net under them. These are fish that didn't get a good purchase on the fly and there's not much we can do but hope we play them carefully enough to land them. Others are hooked more deeply or solidly, squarely in the corner of the jaws or even down in the throat. These are fish that took the fly hard and generally hook themselves almost as soon as they dive after the strike, and aren't gonna get away until you unhook them and let them go. Generally I find the larger fish end up being hooked more solidly, but even small fish like little brookies will take a relatively large (#10) hopper pattern deeply enough to get hooked without issue.
Don't know if this helps, but it just really depends on how the fish hits the fly and, in some cases, whether or not it actually hits the fly or missed it entirely due to "excess enthusiasm" - we've all had fish just blast a fly and then nothing...and some of these fish end up foul-hooked, like they really did miss the fly with their mouths but then upon diving caught it in the fin or flank, had a 13-inch brookie last summer hook itself in the anal fin! (Fought like hell because of it too!) Anyway I hope this makes you feel better, and this is not meant to counter other advice on here about timing the lift when hooking a fish, that does take practice. Best of luck, and remember to sometimes holler out, "Dang it fish, you missed my fly"!
Jonathon
No matter how big the one you just caught is, there's always a bigger one out there somewhere...