Here are 5 common problems I recently noticed on a few websites.
1. Too Many Links in the Navigation Menu
I have seen websites with too many links in the navigation menu that is pushing the search input outside of the navigation bar. So you should either remove or shorten your link names.
2. Floating Widget Issue
I have seen a lot of people with widget content floating outside the widget box. Check out all your non-default WordPress widgets, and if you have this problem check out How to Fix Floating Widget Content.
3. Space Under Your Footer
Certain WordPress plugins will add something to your footer which will add a unnecessary space under your footer. In the example below a little smiley face is being to the very bottom left of the website which is being added by Jetpack or WP Stats. If you are using Jetpack, make sure check the box that says “Hide the stats smiley face image.”
4. Edit Images to the Correct Size / Compress Images
If you do not edit images to the correct dimensions, you will have to depend on the browser to automatically resize a image which can end up making the images stretched and blurry. Large images will take longer to load. I was shocked to see someone upload a 1000 x 1000 pixel image for their beat store image thumbnail that is only suppose to be 140 x 140. Their homepage loaded slow because of 7 of these super large images loading.
5. Transparent Logo Background
I have seen a few people export their site logo with a dark background that doesn’t completely match the background color of the header so you can see a box around the logo. So it is recommend you export your logo with no background as a PNG file with a transparent background to not have this problem.
You might want to also check out 10+ Questions to Ask Yourself Before Launching Your Website.