Sometimes it is important that you reset the Google Pixel 3 or Pixel 4 to factory settings. This is always the case if you have serious bugs with the Android system or if you want to sell the smartphone.
With this method, the factory reset is performed via the Recovery menu. This method is used, for example, if you cannot remember the pin. For the factory reset, proceed as follows on the Google Pixel 3 or Pixel 4
Perform Factory Reset on the Google Pixel 3 or Pixel 4 - Instructions
1. turn off your Google Pixel 3 or Pixel 4
2. Press and hold the Power+Volume Volume Volume Down keys until the boot loader- appears, then release. In the bootloader navigate with the volume key and the power button.
3. Select the recovery mode. The device will briefly flash the Google start screen and then restart in recovery mode.
4. when an Android male with "No Command" appears on the screen, hold down the power key. Press the Volume up key once. Then release the power button.
5. On the next screen, select the option "Wipe data/factory reset".
6. confirm the procedure and wait several minutes until the reset process is complete.
You now need to set up the smartphone again.