Why does Monsieur Loisel advise his wife not to tell her friend about the lost necklace?

Monsieur Loisel advises his wife to tell Madame Forestier that she has broken the clasp on the necklace she has borrowed from her, and that it will take some time to get it repaired at a jewelry shop. Loisel comes up with this lie this so that they have some time to retrace their steps on the night of the gala to see if they can find the necklace that Madame Loisel has lost.  When...

Monsieur Loisel advises his wife to tell Madame Forestier that she has broken the clasp on the necklace she has borrowed from her, and that it will take some time to get it repaired at a jewelry shop. Loisel comes up with this lie this so that they have some time to retrace their steps on the night of the gala to see if they can find the necklace that Madame Loisel has lost.  When they do not find it, Loisel goes to "the police station, to the newspapers, to offer a reward, to the cab companies..." to see if the necklace will surface. When no one steps up after a week has gone by, he combines his inheritance from his father's estate with borrowed money to come up with sufficient funds to purchase a diamond necklace that looks very much like the one that Madame Loisel has lost.