What proved to be the weak point in the young man's story?

The young man who sits down beside Norman Gortsby tells him a complicated hard-luck story with the intention of asking him for a "loan" to enable him to rent a hotel room overnight. According to the story, the young man was a complete stranger in London. He went out to buy a cake of good soap at a chemist's and then got turned around an couldn't find his hotel. He had only taken a shilling and had left all the rest of his money in his room. He used most of the shilling to buy the soap and a drink at a pub. Now he was nearly broke and might have to spend the night sleeping on the grass by the Thames if he couldn't find "a decent chap" to lend him enough to rent a room somewhere. His "people" in the country have the address of his hotel, but he can't get his hotel address by wire until tomorrow. Then he can gladly pay back the borrowed money.

Gortsby is accustomed to sitting on this bench at dusk, and he has heard many hard-luck stories. He has become very skeptical, as well as a sort of connoisseur of hard-luck stories. He listens patiently and attentively. Then he tells the young man:

"Of course," said Gortsby slowly, "the weak point of your story is that you can't produce the soap."

The young man is flustered and embarrassed. He can only say, "I must have lost it."

"To lose an hotel and a cake of soap on one afternoon suggests wilful carelessness," said Gortsby, but the young man scarcely waited to hear the end of the remark. He flitted away down the path, his head held high, with an air of somewhat jaded jauntiness.

There can be no doubt that the young man was a confidence trickster--and not a very experienced one. He should have kept a cake of soap in his overcoat pocket just in case someone would ask to see it. No doubt this was a learning experience for him and he would be sure to have a cake of soap available in the future. He wouldn't even have to buy one, because Gortsby made him a present of the wrapped soap he had found on the ground by the bench after the young man had left in chagrin.

The young con artist turned out to be successful beyond his hopes. He not only got a sovereign from Gortsby but a bonus of a cake of high-quality soap.