What makes Dr. Nemur and Dr. Strauss agree to use Charlie for their experiments in Flowers for Algernon?

Flowers for Algernon is a young adult science-fiction novel written by American author Daniel Keyes. The novel is made up of a series of progress reports written by protagonist Charlie Gordon, age 32.
Charlie is mentally disabled but wants to improve himself, and so he enrolls in reading and writing classes at the Beekman College Center for Retarded Adults. Dr. Nemur and Dr. Strauss are researchers at the college who are working to find a way to increase human intelligence. They are looking for a human test subject, and Charlie is recommended to them by his teacher, Miss Alice Kinnian. Dr. Nemur and Dr. Strauss have already experimented on a mouse named Algernon who showed incredibly positive results. Dr. Nemur does not want to use Charlie for the experiment as he is concerned that Charlie’s IQ is too low. However, Dr. Strauss does want to use Charlie because of his motivation and his desire to learn.

Dr. Strauss said I had something that was very good. He said I had a good motor-vation. I never even knowed I had that. I felt good when he said not everbody with an eye-Q of 68 had that thing like I had it. I dont know what it is or where I got it but he said Algernon had it too.