I'm curious now, how did they do to have a worst army in 1916 than 1914 despite two years of war experience behind them ?
In 1914 the BEF was the best equipped and best trained military force in Europe. It was also the smallest. And while they fought exceptionally during the openng stages of the war they were pretty much wiped out in a few months. By 1916 the british army was rebuilt into a conscript army that had so far played second fiddle to the french, meaning that their soldiers and commanders were less experienced that the french or the germans.
But was it worse? The quality of the individual soldier was certainly worse. A massive conscript army cant choose and train the best soldier like a small professional army can. Equipment? Probably the 1916 army. In 1914 no one was ready for trench warfare, while the 1916 army had adapted with more artillery, machine guns and spades.
But I suppose if you compare both armies to their enemies then both come up short. The german army was always larger that the british, with a bigger war industry to support it. The 1914 BEF may have been well trained and surprised everyone by how well they fought but they were never going to survive longer than a few months.