Alonso has set the bar high at Bayern Leverkusen in the period he was the coach that the team's management and fans will be looking forward to seeing the team improve more. Ten Hang once did something marvelous with that Ajax young team some years ago, his credentials were in doubt when he was at the helms of affairs at Manchester United. I believe with the right players, he can actually achieve great things with Leverkusen.
If Leverkusen can still perform well for next season with Ten Hag, then the team that is mostly formed by Xabi suits Ten Hag. But if Leverkusen performs badly at the start of the season with Ten Hag, then what will definitely be obtained is criticism, where what happened to United will be repeated at Leverkusen.
Everyone certainly does not want that to happen, Ten Hag may not be suitable for United. But hopefully, he will be compatible with Leverkusen and get praise.