On one hand, I think Erik Ten Hag didn't have enough playing time, but on the other, considering his unsuccessful spell at Manchester United, I question why they appointed him as manager. I don't think the new manager will be criticized so harshly, as he needs to spend some time with the team. It seems that poor career management at Manchester United played a significant role in the Dutch manager's dismissal. Otherwise, even with poor results, dismissing a manager in the second week is unacceptable.
This has always been my stance on the sack of Erik Ten Hag. You cannot judge a coach by his past club's performance or after three competitive games. The Dutch coach would have been given more time to show the stuff he is made of. If they are considering his failure at Manchester United, what about his exploits at Ajax? I don't think that Bayer Leverkusen's poor start was the only reason for his sack. Maybe he might have some disagreement or irreconcilable differences with the management of the club
You can judge character. See Tuchel as an example, every club knows he is an asshole and yet he gets jobs because he has had some success and strong experience in the past. Every team knows that Tuchel is not a kind guy and then the question is whether they are fine with it or not. In case of ten Tag everyone knew he is a cry baby and a coach who attacks players in public, doesn't protect them. He is bad at communication and he lets players of his own team in the dark about their opportunities. Leverkusen should have known that, but now they acted as if they didn't and sacked him.