Well, taking a bit of poetic license with that "perfect" word, I find that there are Buck knives for certain applications, like . . .
Hey, can you open this? -- Buck 301 (the one I prefer is a two-spring in 440C)
Can you cut up this roast? -- I find the Silver Creek 223 fillet knife (420HC) does a fine job. Heck, it's not bad on turkey.
I need you to cut up these boxes. -- Well, that depends. I've used the 110, 112, and Vantage. But the Rush, in 420HC, is like my own compact box cutter.
Are you going to make a salad? -- The Silver Creek series is good for this, but I find I prefer Vantage Avid, in 13c26 Sandvik. (Though I've been known to use a 110 for salads.)
It's lunchtime at work, cutting up fruits and veggies. -- The most fun I've had was with the 313 Muskrat, in 440C. Very versatile, light, and simply a pretty knife with classic lines and a fine working edge. Can we bring those back? Please?
We're heading out to spot wildlife; are you dressed? -- Of course I'm dressed. See? I have my 110 (420HC) right here.
And, yes, there are times when I look for an excuse to carry something that spends too much time on the table. Like the Paradigm Avid. Do I need it for EDC duty? No, but I'm gonna carry something, and it might as well have some style.
And there are knives I've not carried more than once or twice (like the Sirius, in S30V), 'cuz today's parameters dictate something lighter, thinner, cuter, or whatever. Fear not, their day will come.
When I need to travel by air (which, thankfully, is rare) my Cutback or Hilo (420HC) takes over as checked-baggage remote EDC.
And, of course, there are certain kitchen duties that are really done best by the Buck Americraft chef's knife. Onions, garlic, the whole host of stir fry veggies. If I know that I'm in for an hour or two of veg hacking, that's the one that accompanies me to the sacred board of cutting.
And, having said all this, the one that simply spends the most time with me in-pocket is the Vantage Avid (no clip). Why? Is it the "perfect" knife for everything? Maybe not, but it's good enough at enough different things that it's with me more than the rest.
Change my environment, my routine, my duties . . . maybe my EDC will change. But for now, well, there it is.