Yeah Claudio Ranieri achieved a complete miracle with Leicester City last year but as Mourinho has brilliantly put it recently 'There is no loyalty in modern football'. The board doesn't care about him, they care about the results and if Leicester get relegated for real that will be a disaster.
By the way I have heard that they are going to erect a statue of Ranieri in front of the stadium. I am not sure if it's just rumors or a real plan though.
Leicester should have been patient with Ranieri he got them their first premier League in a league that is full of big clubs that can spend 10 times more than them and its expected from Leicester to drop down with major player like Kante kept a big hole in Leicester midfield and the other teams improved very well so they sgould gave him more time atleast they managed to score against Sevilla and every one expected that the result of that game will be even more awfull for them