Most of the over 56,000 plugins for WordPress are troublesome in one way or another. That still leaves thousands of great plugins. It is important to make sure any plugins you add to your website meet the following requirements. It is also important to limit the number of plugins you add to a site, in order to prevent constant updating, and potential conflicts between plugins.

Signs of a good plugin:

1. First, the plugin should perform the function you want. You can click the “More Details” link to find out what it is supposed to do. If you’re new to WordPress, you might be amazed how often plugins fall short of the exact functionality you want.
2. It should have at least a four star rating. Rare exceptions are plugins that are hard to figure out, or address tricky issues, in which end users may not be satisfied because they’re working with something unusually complex.
3. Having at least 10,000 active installations usually means the plugin is well-regarded. An exception to this rule, is a specialized plugin that just won’t have that many users. For instance a plugin that calculates hydrodynamic pressures in plumbing is probably not going to be attractive to the general public.
4. There are many plugins that haven’t been updated in years. This can mean all sorts of problems from malware vulnerability to conflicts with modern versions of WordPress, your theme, or other plugins. In most cases, good plugins will have been updated within the past few months.
5. The plugin should come from the WordPress library, accessible from Plugins | Add New on your website’s WordPress dashboard. That indicates that the plugin meets at least minimum compliances. There are some plugins available through outside Internet downloads that are so terrible they’ll break your website. Of course there are many good ones that are not in the library as well.
6. If possible, it should be free. The number of high-quality plugins that have been made as volunteer efforts is astounding. Thousands more are shareware, or more specifically freeware. That means you can download a free version that may meet all your needs. A ‘pro’ version is also available for which you can pay money to get more features.

Free plugins mean that your website won’t be held ransom. Imagine that you’ve purchased a plugin. Then, every year, you have to pay $79 to maintain the license. Let’s say a malware vulnerability has been discovered and the author issues a repaired version. Without paying your annual fee, you can’t have the new, safer version.

Not all paid plugins work that way. Some have a one-time license fee, and you’ll be entitled to free updates forever. Others will literally stop working if you let your license expire.

However, there are also plugins for which you have to pay, but they may offer very specific functionality, and that’s the only way you can get them.

One advantage of paid plugins is technical support. In most cases, with free plugins, you cannot contact the author if you have a question or a problem. And, most of the time, if you have paid money, you are entitled to technical support.