When you post something on your social media resources it shows up on the feed of those following you. The problem is, so do the posts of everyone else they follow. In addition, you have to take into consideration what time your followers look at their social media.
Consider doing your posts at different times during the day. I personally have divided the day into 4 segments that I rotate posts with. There are tools to help you do that, but it is not that hard to do manually.
It can help make your posts more effective.