The assumption of the ignorant is that the number of images, or words, or scenes, is a good metric for anything. It isn't.
I have been writing for years, literal decades, and so I can churn out a thousand words on virtually any topic straight off the cuff, in perhaps less than 15 minutes, depending on just how much care I have for the quality of the writing Itself. Not the content of the writing, the depth of meaning, just the flow, sentence structure, grammar, etc.
But I might spend literally a whole hour composing just the right single sentence for a character in a VN to say, or even longer if it is a particularly important line or scene. So, sometimes 10 words can take far, far longer to write than 1,000 do. And that's with more than 40 years of fascination with psychology and characters. 50 years of fascination with literature and stories.
Which brings us to another thing. What one person spends an hour writing is not necessarily even comparable in depth, meaning, or quality, to what another might write in the same time. Skills and talents matter.
What is true of writing is every bit as true with posing, with image composition, with lighting. One person's render is not the same as another's, nor does time determine the quality of either. What is true of images is just as true with creating a plot, or coding, or designing a user interface.
There's a very famous quote attributed to Mark Twain that goes "I apologize for the length of this letter. I didn't have time to write a shorter one". To anyone skilled in writing this quote is a joy of truth. It takes a lot more time and effort to be concise, to write less words but better chosen to concisely carry all of the same meaning.