ML 63 AMG!!! Why did they replace this beauty?

The Mercedes-Benz M-Class, replaced GLE-Class in 2015, is a mid-size luxury crossover, SUV produced by the German automaker Mercedes-Benz since 1997.
The ML was a signature car for Mercedes-Benz. For years we saw it shining and being on top of any other mid-sized to even full-sized SUV's. The 63 AMG model was the the most powerfull of all powering 510 HP with a 6.2 L  V8 Biturbo engine accelerating from  0-100 km/h in just 4.8 seconds.
So why did this gorgeous car got discontinued and replaced by GLE? Lets hope this beauty return to the AMG gama!!!