Edit: Not necessarily only credible sources needed, different opinions from the user's perspective are also welcome.
The mobile first approach nowadays often (or sometimes at least) leads to less usage of the hover functionality on websites, as they are build with mobile in focus, where hover is not available.
For example many of the solutions given here are majorly to make the functionality available instantly:
Re-thinking "hover" functionality with touchscreens in mind
On one hand, I know that it is a good way to filter it down to the most important information and leave everything else out. But on the other hand, e-commerce product info (especially in the fashion area) is often already minimized to the smallest bits on the product listing page.
The hover state can be a great progressive enhancement feature at that point, that offers users on PC a benefit. It is also recommended by Baymard after one of their large studies regarding product lists: Product Lists: Display Extra Product Info and Images on Hover (70% of Sites Don’t).
On mobile this information is simply left out, as it is not crucial. But wouldn't it be helpful nevertheless?
Currently you have to open each product detail page and check out the sizes and colors, then notice that it's not available and have to hop back to the listing page. If you could instead have extra info appear in the list context, you could be filtering information a lot quicker.
That's also where this thought comes from:
When & How to Implement Interactive Swatches on Mobile Product Listing Pages
Devices are getting bigger, so it is not unreasonable to include some interactive element on the listing page.
Now to my actual question:
Would it not be useful for the user to have some sort of extra possibility to see more info about a product he or she is interested in? Testers in the Baymard study above seem to have found it a positive experience to be able to preview info straight from the list.
What are possible downsides if it were to be implemented as illustrated below?
Or put differently, what effect could this have on the conversion rate or other KPIs in e-commerce?
I think the worst part about this is that the button takes up a lot of space. But it does need some form of affordance to indicate availability of secondary information.
I found an interesting example of this idea as a swiping mechanic:
This eliminates the big button problem, but do users recognize that they can swipe here?