Make a post that no one saw? No likes, no comments, just sitting there, lonely with no interaction?
If it's been over an hour, there are two things you can do to try to salvage some interaction with the post:
1. Like/heart/wow your own post and cross your fingers it stays in the feed long enough to gain a second like/comment/etc.
2. Delete the post and repost the same thing again. Sometimes the time of day that you posted can gravely affect your post. A breaking news story could be going around, making your post almost invisible. Or it could just be a time of day when your followers aren't online.
Neither of these will guarantee interaction but it's a good reminder that not everyone who follows you, sees your posts every time. It's OKAY to reuse material and repost it to get more views, attention, etc.
Selling a product or service? Post an ad for that product at least once per week - try different days of the week and different times. You can quickly/easily do this by copy/pasting and scheduling your posts with the native Facebook scheduler.