Facebook’s On This Day feature, also known as Memories, shows users reminders of posts and life events they’ve shared on the platform in the past. However, many users have noticed that not all of their memories show up on any given day. There are a few main reasons why Facebook’s algorithm doesn’t surface every single memory.
Too Many Memories
The most straightforward reason is that most users have shared so much content on Facebook over the years that it wouldn’t be possible to show it all in one daily digest. According to Facebook, the average user has shared nearly 1,500 posts since joining the platform. With over 2 billion monthly active users, that’s trillions of total posts and photos that have been shared.
Obviously it wouldn’t be feasible or desirable for Facebook to surface every single memory for every user every day. Most people wouldn’t have time to scroll through years and years worth of old posts each day. So Facebook’s algorithm has to select a subset of memories to show each day.
Algorithmic Curation
Facebook’s machine learning systems choose which memories to show based on what they predict will be most relevant and interesting to the user. The algorithm considers factors like:
- How much the user interacted with the original post (likes, comments, shares, etc)
- Who is tagged in the post
- What type of post it is (status update, shared link, photo, etc)
- How long ago it was originally shared
In general, memories that were more popular and generated a lot of engagement when they were first shared will be more likely to show up as memories. Photos and life events like weddings or graduations are also given priority.
User Controls
In addition to algorithmic curation, users have some ability to control what memories show up through features like memory hiding and featured friends.
Memory Hiding
If there are certain memories you don’t want to be reminded of, you can choose to hide that memory so it won’t show up in On This Day. Just click on the three dots in the top right corner of a memory post and select “Hide this memory.”
Featured Friends
You can add up to 30 friends to your “Featured Friends” list. This gives posts that you’re tagged in together with featured friends a higher chance of being surfaced as memories.
So if you really want to see memories with specific close friends, add them to your featured list. Though it’s not guaranteed you’ll see all memories with featured friends.
Limitations of Machine Learning
While Facebook’s algorithms are sophisticated, they can never be 100% accurate at predicting what memories each user will find most relevant or want to re-engage with. Machine learning is far from perfect, so there will always be “missed” memories that don’t get surfaced but potentially could have.
And different users will have different preferences on types of memories they enjoy revisiting. The algorithmic models are designed to appeal to general trends, but can’t customize themselves perfectly for each of billions of individual users.
Promoting Recent Engagement
Facebook also has a business incentive to use On This Day as a way to promote more recent activity on the platform. Surfacing current memories helps drive further engagement, commenting, and sharing of recent content.
So while users may sometimes want to see older memories from years ago, Facebook’s algorithm is also designed to sprinkle in more recent memories from the past year or so to help keep people active on the platform.
Too Much Personalization Could Backfire
Interestingly, Facebook has found that over-personalizing memories can actually decrease engagement for some users. In this
2016 research paper, Facebook data scientists explain:
“If people feel the content is too personalized, they may perceive it as creepy. On the other hand, if the content does not feel personalized enough, people may perceive it as spam.”
Therefore, Facebook strikes a delicate balance of tailoring memories to users’ interests, while also keeping some level of serendipity and variety. The data scientists found that increasing personalization of On This Day by 10-30% was optimal for engagement, while further increases beyond that actually decreased liking and commenting activity.
Filtering Problematic Content
In some cases, Facebook may intentionally suppress certain types of memories that could be seen as objectionable, offensive or in violation of their community standards today. They may choose not to resurface old content that promoted harmful misinformation, hate speech, bullying behavior or other types of abusive content.
Facebook’s values and content policies have evolved significantly over time. So while a post may have been acceptable to share years ago when it was first created, Facebook now has enforcement and moderation policies that prohibit some types of harmful content being recirculated.
Technical Errors
Lastly, there could be occasional technical bugs or errors that prevent some memories from showing properly. Given the massive scale of Facebook’s data systems, glitches can and do occur. If you notice entire years of memories missing, it may be an issue worth reporting to Facebook support.
Conclusion
To summarize, there are reasonable explanations for why Facebook Memories does not surface every single past post on an exact anniversary date. The huge scale of data, use of machine learning models, business incentives, and user preferences necessitate curating a filtered set of memories to show each day rather than everything at once. However, users can still take steps like hiding unwanted memories and featuring close friends to improve On This Day. Understanding why Facebook doesn’t show all memories can help manage expectations and make the most of this nostalgic feature.
| Reason | Explanation |
|---|---|
| Too many memories | Users have shared too much content for Facebook to surface it all |
| Algorithmic curation | ML models predict the most relevant, popular memories to show |
| User controls | Hiding memories and featuring friends customize On This Day |
| Limitations of ML | Algorithms aren’t perfect and miss some relevant memories |
| Promoting recent activity | Facebook mixes in newer memories to encourage engagement |
| Avoiding over-personalization | Too much customization may seem creepy and decrease engagement |
| Filtering problematic content | Old offensive/harassing content may be suppressed |
| Technical errors | Bugs or glitches may prevent some memories from showing |