To limit the probability that the placement or amount and spacing of vertical reinforcement will not be adequate to ensure the reinforcement is encased and bonded to the concrete, which could lead to an inadequate resistance to expected loads, which could lead to concrete cracking or the displacement of walls.
This is to limit the probability of:
For floors and elements supporting floors, this is to limit the probability of excessive movement, deflection or vibration, which could lead to negative effects on the psychological well-being of persons.