It's silly that you can't understand that this is only an issue that Microsoft devices have (recently) been having. You won't ever hear an iPad user complaining about this.
iPads do not even offer the functionality to view these statistics, but that doesn't mean they behave differently. As I previously stated, and as you clearly ignored, every device that uses a Li-Ion battery is subjected to battery wear. The battery wears, and it then requires recalibration. Depending on usage, you will also require recalibration more or less frequently.
Furthermore, iPads are basically the most casual devices on the market after the common iPhone. I bet that most iPad users will be shocked to hear that their battery capacity decreases over time with usage, so how can they be expected to complain about something they have never heard of? Again, this does not mean the phenomenon does not exist - simply that you are ignorant to it.