You can use the third party app Coconut Battery to check the battery's current state in regards to its original Design Capacity (it is the second bar in the app which shows this and is what @ku4hx is referring to when referencing 80%).
Most likely your battery is teetering near the 80% mark. I have seen the "Service Recommended" condition come & go when the battery nears the 80% mark especially with older batteries. Older batteries tend to develop bad cells where the Full Charge Capacity (FCC) can vary by as much as 500mAh during use. This amount of change is enough to have the battery's FCC below the 80% mark and also above it especially when the battery is draining/charging quickly. The "Service Recommended" condition can also indicate a hardware issue has been detected with the battery....again, this can sometimes come & go as well.
From my own personal experiencing with supporting our organization's thousands of Macs, I have learned a lot about these batteries since many times I could not reproduce or confirm a user's claim of battery issues. So I spent a lot of time monitoring these batteries at a lower level and finally developed some methods of better testing & discovering worn out & failing batteries (requires using the command line...Intel Macs only since Apple changed the information with Apple Silicon Macs).
@ku4hx is absolutely correct regarding the cycle count. It is only useful for two cases. If the cycle count is nearing 1,000 cycles, then you know you have a well used battery that will likely need to be replaced soon. Second, Apple uses the Cycle Count to determine if a battery can be replaced for free under the original system warranty. Otherwise, just ignore the cycle count. Keep in mind if the charger is connected most of the time, then the battery will have a very low cycle count even after years of use, but the battery will still be years old. Batteries use chemical reactions which degrade over time as well as degrading the internal battery contacts as well. In fact leaving a charger connected all the time is bad for the battery since the battery needs to be exercised once in a while which is why Apple implemented a new battery health management system with macOS 10.15.x (forget which patch introduced it) so that macOS will exercise the battery now so the user doesn't have to worry about leaving the charger connected all the time.
