I was thinking about the use of carousels in homepages, I have noticed a lot of web pages use and I really don't think they are useful sometimes, however I'm just a developer but I really like to do my homework and I decided to learn a big more about UX, problems come when I try to find a logic explanation why we should or not avoid this.
Whether you use a particular html feature or jquery widget or whatever really depends more on what problem you are trying to solve.
Identify the problems to be solved, then design solutions to those problems. Don't just grab solutions as seen elsewhere and then just use them.
Regarding sliders (aka carousels) ...
Use when your problem is:
But only if:
The fallback for non-js visitors would likely be to present a few thumbnails with a more... link (eg. more news... or more featured products...). That satisfies the problem requirements as detailed above.