Prologos mentioned that they got 1914 right... sorry friend but no they did not! They got it entirely wrong. It was to be the first year of world peace! Nobody could get it more wrong. Russell was gravely disappointed at the failure in 1914 to realise his own prediction baby of the end of human rule on earth and the establishment of God’s government worldwide. Watchtower revisionist history of course sees it differently. The WTBTS have never got anything right and never made a correct prediction. They have never said anything useful apart from directing money to their own bank.
The doctrines they guard, which are often confusing and contradictory such as the generation thing, are just to shift the focus of the flock away from thinking about the glaring lack of divine approval they demonstrate. This is what doctrines are for.