I agree with RP_Joe. Not that simple. Consistent clickthroughs are not a measure of quality. The reverse is true as well. Poor clickthroughs are not a measure of poor quality.
Fewer visits means fewer clickthroughs. Is it because the title tag & meta description are not good? Is it because the site positioned beneath it has better title tags?
Or... is it because the listed site is irrelevant? If that's the case then perhaps the algo would be looking for close to NO visitors, or better yet, a statistically low amount of visitors for the typical site listed on that SERP. Fewer visits can be attributed to many things. No visits or statistically improbably low visits might be a flag.
Now compare that metric with another one, time spent on a site. Time spent on a site could be indicative of user dissatisfaction, especially if followed by clicks on other sites listed on the SERPs. It could indicate satisfaction if the user ceases to click on the SERPs. Clicks on several SERP listings could be a flag that something's wrong with the rankings. Etcetera.