Is it possible for something to be the best?

Twl is right -- but there is at least one other dimension of subjectivity. Two people listening to two systems might have different opionions of "best". Since every component makes some sort of compromise (e.g., a bit tighter bass vs. a bit wider soundstage) and every listener has her/his own priorities of what is most important, there will be a wide variety of "best" at any price point. The trick is to understand your own priorities, explicitly make the trade-off decisions and then be happy with the best available for your tastes. I have found that people are often unhappy later because they did not acknowledge what they are giving up when they purchased their gear (this is not a price issue, it arises from no component doing everything perfectly). Of course, people also become less happy with their gear as musical tastes change, listening experience increases or priorities change. Good question. I'm looking forward to reading other's responses.

"Best" is a very questionable term, because it invites uncertainty, a probably very unfortunate competitiveness, unfortunate for the pocketbook and one's peace of mind and last not least the futile and time consuming attempt to rationalise in objective terms, what we purely subjectively percieve to be "best". It also probably leads to the misconception, that, if we try hard enough, we can REALLY simulate the live event sooner or later in our listening rooms, if we take live music as our benchmark.
Since we all seem to agree, that "best" can only be subjective, why not settle on a term, which though subjective, will give us more comfort for the soul, lets us enjoy the music more and approach other "best" systems with a more relaxed and friendly fashion. What I have in mind, could perhaps best be described with the term " musical ". Of course it is just as subjective and as a descriptive form similarly lacking in precision as the word "best". It however describes a quality in a system, which will satisfy the soul of a true musiclover. "Best" certainly doesn't, because "better" is always just around the corner, at least that is what our dealers or the journals and all the advertising hype tell us. So lets nor fall into that trap. It is a sure way to fall prey to an addictive syndrome, we are all familiar with. Once we find our system musical, it is of course not BEST, but good enough for us, because it helps to induce a state of mind of relaxed and yet attentive and grateful happyness. After all, what more would you need from a hobby. Cheers,
Detlof

Yes this is absolutely possible! My wife is the best, she has remained with me for more than thirty years regardless of how much money I spent on my audio gear.

That is a state of the art performance.

Albert, if Detlof is right, then it stands to reason that your wife is also musical :-)

No, if you mean "best for everybody." First of all, we all listen in different rooms, and a speaker that sounds great in one room can sound awful in another. Second, no audio system can replicate a live concert perfectly, and we each have our own idea about the best tradeoffs. And, finally, none of us can listen to everything. So the most you can say about a system is, "This is the system I like best in this room, of all the systems I've heard here."