Sometimes the shot has to be from a surprise location in a part of the attack that the gk and defenders aren't expecting it. example: Maupay's 95th minute goal against Palace.
In case you feel shy about using one of the new defibs you just slap a pad on top of the chest and the other on the side of the chest and then turn it on. It does everything else on it's own. In a situation where someone is dying in front of you, you should never be afraid to use the device.