Too few GFCI or AFCI outlets
Ground Fault Circuit Interrupter (GFCI) and Arc Fault Circuit Interrupter (AFCI) outlets protect you from potentially dangerous electrical flows and shut off if triggered to prevent fires or electric shock.
GFCIs are commonly found where electrical circuits could come in contact with water like in kitchens, bathrooms and laundries while AFCIs are used more broadly in living rooms, dining rooms, family rooms, hallways and bedrooms and work by sensing an arc in the circuit that could cause danger (like an animal chewing through them, for example).
Another protection device required by code is tamper-resistant receptacles which are designed to stop objects being inserted into an outlet.