Images are one of the single biggest things which slow websites down and no matter how much optimizing you may be doing, the fact is if you have an image heavy website, then a considerable chunk of your load time goes to loading images.
Thankfully there is a way to circumvent this entirely and it baffles me when more web designers and web developers don't take advantage of these methods because it's not a difficult thing to implement.
The way to circumvent this is with a tactic called lazy loading.
By loading images when they are actually required, it brings down the initial load time of the page, which keeps users on your site and helps with your ranking on Google.
Some of you may already be aware that Chrome has recently released an update with lazy loading built in, which is great!. But we need to wait for this to become more widespread before we can rely on this entierly.
I have included an example on this plugin of just how much of a massive impact lazy loading can make on the load times.
On a good connection, the example will show that with lazy loading the page loads in under 1s... Click the link to the very same page with lazy loading disabled though and you are looking at a load time in excess of 10s.
I use the same code on my own website and I'm sure you will agree that my website is very snappy and quick. Without lazy loading, I'd be looking at much slower load times, even with optimal images.
There is no reason not to use some form of lazy loading in your web designs.
It's not hard and has a huge impact and over the years it's getting easier and easier to implement, so much so that we will soon have baked in functionality without the need to include JavaScipt plugins.