As a blogger for the recent years, I have learnt a lot of things. This is one of them. NEVER Ignore the Alt tags in images. In my beginning days, I was too lazy to put Alt text for each and every image. But it was a big mistake.
I have experimented so many things. Alt tags play a big role in the ranking of the articles. Apart from that, it can be in good positions as well. Which means, you can get visitors from that single image. If your image is ranking well for a search term and some other bloggers or website owners find it and use on their blog, you will surely get a credit link to your website.
So many authority websites linked to my blog just by crediting me. So, always try to rank your images as you are trying to rank your articles. Alt tag plays a major role in this. Also share your thoughts on this.