From Rising Sun And Tumbling Bear, by R. M. Connaughton (Orion, 2020), Kindle pp. 383, 392:
The Japanese officer provided the essential link between the men and their Emperor. The majority of junior officers were of peasant origin and had been educated in the tradition of the samurai and the school of Bushido. With very few exceptions, the Russian officer did not enjoy such empathy with his men because the men were of lowly origin. That in itself is no reason why, as Britain’s armed forces proved in the twentieth century, they should not fight as an effective and harmonious whole. One reason why Russia’s officer corps lacked the common standards and professionalism enjoyed by the Japanese officer corps was noted by a military observer: ‘… the remarkable number of Guards officers, who were either promoted to commands, or else were appointed to the staff. A few were good men in the field but family influence was usually the deciding factor, and the officers of the line – and Russia – suffered accordingly.’ Another reason was the advanced years of many commanders, effectively blocking the progress of energetic, younger officers with new ideas.
In 1914, the Russian First and Second Armies were commanded by Rennenkampf and Samsonov, the former sparring partners at Mukden station in 1905. Colonel Max Hoffman had been one of the German observers during the Russo-Japanese War and used the possibility of a breakdown in communication and co-operation between the two Russian generals to offer Ludendorff and Hindenburg a plan to divide the two Russian armies. When German signals intercept units picked up the Russian future intentions being sent in clear and not coded, Hoffman was able to persuade his doubting commanders that this was not a deception plan but rather sheer, unsurprising incompetence.