What exactly is critical listening? Who does it?

If a system is utterly musical and pleasing to my ears, I don’t think how it sounds. We keep thinking about its sound (critical listening) because the system is not musical and unpleasant to our ears and it became an object.

Can you think about how it sound when you listen below music which, I think, is more musical than the original music?  Alex/Wavetouch audio

Eric Clapton - Tears in heaven

Original music 

I agree with @ozzy62’s comment concerning “critical listening” could mean something different to each individual.  For me, critical listening is when I am simply listening to minute details in the music to see if a new product I am auditioning is improving the sound quality.  I’m critical listening so I can make a decision on a product I’m contemplating on buying.  I imagine most of us would do that before we spend money on our gear, if we have an opportunity to audition a product.  So, 99% of the time, I’m NOT critical listening, but enjoying the music because I finally got my system dialed in and I have no desire to audition or replace anything.  That’s what critical listening means to me,

@mihorn I don't get how you'd NOT appreciate and/or listen to the sound of your system if it's pleasing to the ear. For instance I cannot listen to my system without marveling at the way performers are presented with these uncanny three dimensional  life size images on these utterly unique sound stages that individual recordings offer up. And I could go on and on about timbre, tonality, resolution, transparency, etc, etc. The sound and music go hand in hand, heightened sound quality brings the performers into the room and make it all the more believable. I spent decades pursuing this sound and now I'm supposed to look past it or ignore it! 

I still don't get the idea that listening to the sound is a critical/bad thing when listening to high end systems. I purposely didn't listen critically with lesser systems because it exposed flaws in sound, minus the flaws one should desire to have at least some consciousness in regard to sound, the sound is in service to the music and performers.

OP, only you can decide if you want to do critical listening--if so, when and why.

I’ve done a lot of it, specifically:

• When I’m writing a review of a headphone, amp or DAC (to post on an audio board ... not a professional reviewer)
• When I’m writing descriptions of the sound of a given DAC, preamp, amp, pair of speakers
• When I get a new (or new-to-me used) component and first hear it in my system
• Or when I hear someone else’s system/equipment

Critical listening is an entirely different mindset from casual or enjoyment listening--the kind I do most often. Critical listening requires less emotion and more analysis, ie, What exactly am I hearing? How can I describe what I’m hearing in words someone else can understand?

Critical listening isn’t fun, but sometimes it’s necessary. And one’s hearing, like any other brain activity, can be practiced and improved, resulting in more focus and awareness of what is being perceived. For example, time spent listening critically helps me indirectly (yet significantly) when I listen to unfamiliar music and try to put it in the perspective of music known to me (perhaps beloved by me). It could be a jazz cut or a classical performance. There’s a halo effect with critical listening, at least for me; sometimes it helps even when I’m not consciously listening critically.

So I'm really having trouble with what exactly is the definition of critical listening, this what OP asked in original post.

Some state that listening to the sound of one's system is critical listening, this inferior to a mode where one transcends the sound of their system  and/or eliminates consciousness of it's sound quality or qualities. 

So, my question is why is this a superior mode of listening, what makes it inherently superior? And why is consciousness of sound quality or qualities necessarily a critical mode of listening? And then we have the music and the performance of that music, is there not some level of critical listening in that?  We all have favorite artists, genres of music , favored performances of that music. So somehow we magically escape critical listening when we just listen to the music, some magical spell transports us to this world of no judgment, comparison, consciousness. 

My take is whenever we are listening INTENTLY  to music reproduced over high end systems we are inherently in critical listening mode, this applicable to the music, performance of that music and the sound quality or qualities of our systems. I assume we all got into high end audio in order to more realistically present music in our home environment, we wish to feel a closer connection to the artists and their performance of music, this requires critical attention being paid. Casual listening on the other hand is not critical listening, our attention is diverted to other things. Critical listening is listening with full attention, is not necessarily judgmental or doesn't have to be judgemental. Critical listening is listening with heightened senses, this is not a bad thing.