Why does my phone make a sound when i take a photo even when my phone is silent?

When iPhone is in silent mode, it does not make a sound when you click a picture. But if you bought your iPhone from certain countries like Japan, it will always make a sound when you click a picture. This is to prevent snooping and clicking pictures of people without them knowing about it.

• Set the volume to zero using the Control Center. Then Camera won't make a sound while clicking pictures.
• When you click a Live Photo, the Camera app does not make a sound.

Other solutions to fix unusual camera sound in silent mode:

• Make sure the iPhone is actually in silent mode. With old iPhones, the Silent switch may be wobbly and not put the iPhone in silent mode.
• Restart your iPhone.
• Reset All Settings (this will erase things like Bluetooth devices, Wi-Fi networks, VPN, etc. Personal data won't be affected): Open the Settings app → General → Reset → Reset All Settings.

Hope it helps.

There are many countries where putting camera shutters to silent is illegal for e.g. Japan

Hence if you have bought an iPhone from any of these countries (Japan), you cannot put it off.