Cache mechanisms are a real challenge for A/B testing. When your website is behind a cache, it’s possible that all your visitors end up seeing the same (original) variant, thus making A/B testing impossible.

Some A/B Testing plugins for WordPress are simply not compatible with caches and make you choose between performance and conversion optimization. Nelio A/B Testing, on the other hand, will work properly even if your WordPress site is behind a cache system or a CDN.