Complex sentence: Retail loss prevention is a set of practices employed by retail companies to preserve profit by reducing losses due to deliberate and inadvertent human actions, colloquially known as "shrink reduction".
Split into simpler sentences: Retail loss prevention is a set of practices employed by retail companies to preserve profit. Profit preservation, in this context is any business activity specifically intended to reduce losses due to deliberate and inadvertent human actions, colloquially known as "shrink reduction".