Many webmasters start their website without a long-term plan for the future. That could always come back to bite them where it hurts down the road. Take featured images for instance. Your current theme might not use them heavily, but if you don’t define them for each post and upgrade to a magazine theme, you may have to do a bit of coding to fix your thumbnails. It is in general a good practice to require your bloggers to add a featured image to their posts, especially if you run a growing online magazine. These 3 plugins force you to set a featured image for your posts:
Require Featured Image: requires post types that you choose to have a featured image set before they can be published. It makes life easier for editors.
Force Featured Image: forces your writers to add a proper featured image to their posts before hitting the publish button.
G Оbligatory Featured Image: the plugin has two modes to make it obligatory for your writers to add featured images to their posts. You can pick and choose which post types should follow this rule.
Setting a featured image for each post is very easy. But many of us simply forget. The above plugins remind you to do your job and make life easier for your editors.