Recency bias is a fancy way of saying that people tend to remember things that happened recently more than things that happened a long time ago.
Think about when you went to the park yesterday and had a really fun time. You're more likely to remember that fun time you had yesterday than the fun time you had last month. That's because it's more recent and fresher in your memory.
When it comes to making decisions, sometimes people can be influenced by recency bias. They might remember the most recent information they saw or heard about something and forget about other information from the past. This can sometimes make them make decisions that aren't as good because they didn't think about all the information at the same time.
So, it's important to try and remember everything you know about something when you're making a decision, even if some of that information is from a while ago.