why my lg nexus 4 is not switching on???

[AC Question]

i tried to reboot or reset my nexus 4 . but the starting screen does not appear. i don't know actually what is the problem . there is a bug of this phone. i never buy this again. there is no solution from the mobile shop . they also tried but the screen not appear. if you have any kind of solution then please reply.

 

[Laura Knotek]

Are you able to reboot the device in recovery mode? https://support.google.com/nexus/answer/4596836?hl=en

Option 2: Reset device in Recovery mode
If you can't open the Settings app because of device issues, you can use Recovery mode to factory data reset ("format") your device.

Tip: If your device becomes unresponsive at any point, you can restart it by holding down the Power button for several seconds.

After following all the Before you start steps above:

If your device is on, turn it off.
Press & hold the Volume down button. While holding Volume down, press & hold the Power button until the phone turns on. You'll see the word "Start" with an arrow around it.
Press the Volume down button until you highlight "Recovery mode."
Press the Power button to start recovery mode. You'll see an image of an Android robot with a red exclamation mark (you may also see "No command").
Press & hold the Power button. While holding Power, press the Volume up button once. Then release the Power button.
Press the Volume down button until you highlight "Wipe data/factory reset." Then press the Power button.
Press the Volume down button until you highlight "Yes" (or "Yes - delete all user data"). Then press the Power button to select it.
After the reset is complete, press the Power button to select "Reboot system now."
When you're done, restore your data.