To limit the probability of inadequate support for ties, which could lead to the excessive flexing of ties under lateral loads, which could lead to inadequate load distribution among the wythes of multiple-wythe masonry walls, which could lead to an inability to resist transverse or vertical loads, which could lead to cracking or buckling.
Where masonry construction is required to provide fire resistance, this is to limit the probability of compromised fire resistance of the assembly, which could lead to harm to persons.