Reproduction steps:
1. Open the attached project "ReproProj"
2. Open the “/Assets/Scenes/SampleScene.unity” Scene
3. Enter the Play Mode
4. Place the mouse pointer on the Button with the text “Counter:”
5. Observe the number

Expected result: The number can be 0 or non-0, and the documentation is clear about it
Actual result: Number is above 0 but the documentation leads to believe it should be 0

Reproducible with: 6000.0.17f1
Could not test with: 2021.3.42f1, 2022.3.44f1 (Assets\UI Toolkit\CounterButton.cs(8,2): error CS0246: The type or namespace name 'UxmlElementAttribute' could not be found)

Reproducible on:
Play Mode
Windows Standalone Player
VLNQA00325, Samsung Galaxy Note10 (SM-N970F), Android 12, CPU: Exynos 9 (9825), GPU: Mali-G76
VLNQA00318, Oneplus OnePlus 7 Pro (GM1913), Android 11, CPU: Snapdragon 855 SM8150, GPU: Adreno (TM) 640
VLNQA00231, Samsung Galaxy A5(2017) (SM-A520F), Android 8.0.0, CPU: Exynos 7 Octa 7880, GPU: Mali-T830

Testing environment: Windows 10 Enterprise 21H2
Not reproducible on: No other environment tested