Why was the telephone not widely adopted for military use soon after its invention?

Following the invention of the telephone in 1876, its adoption for military use was not immediate. This delay is primarily attributed to two factors: the absence of the compelling stimulation of war during that period and the fact that long-distance telephone communication technology had not yet been achieved.1

While the telephone was utilized in conflicts such as the Spanish-American War, the South African (Boer) War, and the Russo-Japanese War, its application remained limited and contributed little to the advancement of voice telephony at the time. Although military adaptation of the telephone occurred prior to World War I, the technology had not yet reached its full period of growth for widespread military integration.1