His reasoning was this: the making of would involve, in his mind, the idea that something would have to be applied to the original frame to produce the image. To some degree, he's right in that very few final images are great right out of the camera, nothing added to improve or alter. But, what he was after is learning to create in-camera, to get that first step 95% right (or better) before having to rely on Photoshop or Lightroom or something else to pull the impression out of the image, sometimes kicking and screaming all the way to the final print. He wanted to hone the "taking" to minimize the post-production "making" after-effects and adjustments. (The concept he had differs dramatically from a photographer seeing something in the original scene that is intentioned even then to be requiring of post-production techniques to "make" that personal minds eye photo-impression...which is very much in line with Adams' mindset.)
If you can get the exposure right while still standing there in your scene, so much the better. It comes with learning how your camera sees the world it's pointed at. I have long said, and written, that cameras are idiots. Their expense, bells and whistles, image size, etc., doesn't matter. They will try to think and act on your behalf, like a free-wheeling agent, but have absolutely no idea what's in your mind, what you're looking at, what your intentions are. But, quite blindly, it will be most happy to try to do the work for you, like an over-eager little puppy dog wanting to please master.
The adjustment process is rather one-sided: you learn the processes of your camera, not the other way around, not it of you. You learn the sensor's idiosyncrasies, just as we did in years past with learning how particular films recorded what was captured on them. Some digital cameras have manually-adjustable controls to tweak it more to your minds eye - color sensitivities, contrast, saturation, white balance, etc. - but the camera, by itself, won't change for you just because you might wish it to. Once you know just how it will behave, with experience, you can adjust your eye to match how it sees, and get better initial captures without having to pull out your magical photo-editing tool kit when you get to your laptop or home pc. Some of this also involves not shooting scenes you know will exceed what the camera can actually handle, whether digital or film. Some overly-contrasty original scenes will require ample HDR frames with post-production effort to render it worthwhile...but, there are some scenes that are simply better left to our eyes to appreciate and enjoy. Some in-camera techniques outside of the camera, itself, may be brought into play - filter use (maybe a polarizer, or a graduated grey or color) and/or external light manipulation (flash/strobe, scrims or reflectors, etc.) - to manually adjust what the camera can't. With this, you ARE moving closer to the taking rather than making, especially if the image is a straight color photo-journalistic capture, simple color portrait, or a 'fine as it is' color landscape scene. Congratulations, you've done what many photographers strive to accomplish!
Ansel Adams was renowned for his black-and-white image production. The original frame was but one step in the series of them that led from "seeing" the impression in the original scene, then using the in-camera techniques to capture it, knowing there would be follow-up adjustments to merge latent imagination with print reality - specific film development to match the film's sensitivities and exposure; print creation and development to make from that negative what he had in his mind. Nothing about the execution was instant. Nothing about the process was without experience with the various tools and the wisdom to understand how they are applied for a given result.
Granted, a similar process with image-development still exists today, from becoming aware of a scene or situation to want to capture, to the actual recording process, to the follow-up with whatever software is used to craft the raw file into your particular impression. Except for the change in technology involved, Adams' "hierarchy of an photograph" hasn't changed, from inception to presentation. (and the first step never was to "take the picture": that point is actually third down the list!)
So, which direction in this processing is right or wrong: taking or making; making or taking? Reality and honesty will claim both are interconnected. It depends upon the situation involved. It depends upon what the intended final impression is supposed to look like, relative to the original scene. For many, getting the exposure and framing just right the first time will have the taking equaling the making, with only a resizing and adding personal copyright text being applied after-the-fact. Been there and done that 90% of the time. Others will still require your attention to shape the initial reality into what a more internalized version of was experienced or felt within you. There, you still have making as theat working process to drive through.
But, that's the nature of image making. Enjoy it.
