In his later years, he spent much of his time sharing what he learned. More than his considerable business achievements, which include taking on the one-time state monopoly of Nippon Telegraph & Telephone Corp. to build Japan’s No. 2 mobile carrier, he became known for his management credo. Kyocera’s website lists 46 books he wrote or co-authored, mostly on the subject of management or philosophy. Thousands of students flocked to his Seiwajyuku school of management, from SoftBank Group Corp. founder Masayoshi Son to Hakuho, the most decorated sumo wrestler in history.