Bulk optimization process does not behave correctly. What's happening?
We have received some reports where the bulk optimization process wasn't behaving as it should. For example, starting it would do it at 11% optimization, then would skip directly to 100%. In 20 seconds or so, again it would show 11% optimization and again would skip to 100%.
For cases like this one, you should take a look at your cache plugin. For example, W3 Total Cache has an Object caching feature which interferes with ShortPixel Image Optimizer. This specific feature from W3 Total Cache also interferes with normal WordPress functions like wp-cron, making scheduled posts to not get published.