Answer
It is easier for natural selection to remove a deleterious recessive allele from an inbreeding population, BUT doing so may negatively impact the population overall because in an inbred population, all variable traits are affected (p. 33). Therefore, in an inbreeding situation, the genes will die out because it is more likely that organisms will die out altogether - and their genes along with them.
Work Step by Step
1) In nonrandom mating populations, genotype frequencies do not adhere to the Hardy-Weinberg equilibrium (p. 33).
2) Inbreeding depression causes a higher frequency of organisms with multiple copies of deleterious genes (p. 34)
3) When inbreeding is common or encouraged through animal husbandry, "individuals homozygous for deleterious genes die, thereby removing those genes from the population" (p. 34).
4) Then, the rest of the population does not have those genes.
