As soon as the wicket of Azhar fell, there were still 30+ overs to play and 7 wickets to take. They could have gone on the full offensive and really pushed for wickets. Instead, as soon as Anderson got his 600, they lost complete motivation. Completely sat back, let batsmen take easy quick singles, let Babar absolutely whack Bess all around the park to the point where the batsmen were comfortable and in, then they gave up completely and put Root on.
Had the chance to inject some impetus and excitement into their final Test session of the year, and give it a bit more of a thrilling finish going for a win, which would've helped them in the WTC. Instead, they all looked like they'd rather be sitting at home.