It isn't that you can't post multiple times per day. It is more about how much content and how high is the quality of the content. The effort that is put into a post will matter to those voting and curating your content. Read those two posts and you will understand better. Most communities have their rules posted. Here are the rules for Photography Lovers Community.

Rules

• Original photography only. If you are not the owner of or the model in the photos that you are sharing, you will be flagged and muted.
• Plagiarism is not tolerated and will get you flagged and muted.
• Stock Images, unless they are yours, will get you flagged and muted.
• All NON-Photography posts will be muted.
• Single image posts with little or no context may be muted.
• Selfies and Daily Snapshot posts may be muted at curator discretion.
• Any and all use of Artificial Intelligence in your images or text must be disclosed in your post.
• Artificial Intelligence only posts will be muted.
• Spamming posts into this community will also get you muted.
• Cross Posting is allowed, but will not be curated.
• Active Users on Steemit and/or Blurt will be muted.