For any Website it is important to load fast or as fast as possible.
The Size of Images both in px AND kb is one important factor.
There is no need to upload an Image which is 6000×4000 px and 1.7 mb.
It won’t display at that size anyway and it WILL slow down your Website.
Better to optimize your Images BEFORE you upload them.
I am aware of some Plugins, which promise to optimize your Images while they are being uploaded. Such as Smush for example.
Those MIGHT do a reasonable Job, but optimising them yourself off line will give even better Results.
Taking the example of a Real Estate Website: They usually have 1 featured , larger Image plus a few more in a Picture Gallery for each Property.
Having 50 Properties online can easily result in a few hundred Images.
Many Agents also leave their old, sold Properties online, which might be beneficial for marketing purposes, but…
Using the new .webp Image format, we have achieved compression or reductions of nearly 90%, without loss of quality ( reducing file size in kbs and pxs )
There are many good Image Optimization Programs available
We use the best.
In this example the Image on the left Side ( or top if you view this on a mobile device ) is 1920x1280px and weighs in at 1.26MBs. Way to big for the Website!
The same (optimized ) Image on the right Side ( or bottom if you view this on a mobile device ) is 1920x1280px and weighs in at 203kbs, a Reduction of 87% !