Why does Play Store on Android Wear claim ten updates when there are only two? My Ticwatch S2 notifies me when there are app updates available, which when tapped gives the option to update all or open (I have auto-update apps turned off). I picked open.

 

However, instead of the expected 10 pending updates, I'm only shown 2:



Note it shows 2 updates available (just barely visible at the top) and scrolling down just shows recently updated. When I checked each installed app individually, no other apps showed having an update (I'm not 100% the watch version of the Play Store does that, though).

This has been going on for a while. I've already tried:


Using "update all" instead of individually reviewing updates by hitting "open".
Clearing data for the Play Store, that cleared the list of recent updates and reset the settings for the Play Store back to defaults, but didn't solve the issue.


One thing I have noticed is that on the Play Store's main screen, it lists 8 apps on my phone that I don't have on my watch. Odd coincidence?
Not a coincidence. The Wear OS 2.x device's Play Store shows the pending updates both on the Wear device and the phone. This is because Wear OS 2.x allows standalone wear apps, and they can be installed/updated independently from the phone apps.
Thus, if the notification says &quot;X new updates, Y updates total are pending&quot;, it means there are X independent Wear apps to update, but a total of Y apps both on Wear device and phone to update. Updating all from the Wear device will only affect the independent Wear apps, so the user still needs to use the phone's Play Store to update the apps on the phone.
From Android Developers - Package and distribute Wear apps

Distribution to Wear 2.0 watches
On devices running Wear 2.0, when a user installs a phone app that has an associated watch app (either an embedded APK or an APK uploaded via the Play Console), the user gets a watch notification about the available watch app. Tapping the notification opens the watch Play Store, giving the user the option to install the watch app.
Additionally:

[...]
When you upload a watch APK via the Play Console, you can update your Wear APK independently from the phone APK, and users receive updates via the watch Play Store.
[...]

(Emphasis mine)

Previously on Wear OS 1.x (and before, i.e. Android Wear), wear apps are embedded in the phone apps. To update the wear apps, the user has to update the phone apps first, then the Play Store will install the embedded wear apps from the phone to the Wear device.
Also from the same article,

Distribution to Wear 1.x and 2.0 watches
The standard distribution model for Wear 1.x was embedding a watch app inside a phone app. [...]. When a user installs your phone app, if you have a compatible Wear app in the Play Store, it will automatically be installed on Wear 1.0 watches.


Additional note: Ticwatch S2 runs on Wear OS 2.2.