Leadership speculation happens when a public rating of a leader is poor. It means that the leader didn't perform well on their job or on the occasions other people's problems arose and the leader didn't handle it well that causes poor perception from the public. Poor ratings are often associated with reasons that reveal the true colour of the leader.
The disciple of Jesus discussed amongst themselves about the leadership change. It had nothing to do with their Master's rating of approval. The disciples knew that their Master performed well and highly accepted by the crowds. Several times the crowds even wanted him to be their leader, their future king but Jesus would not accept it. Not accepting the proposal to be their king, Jesus ran away from that place, left for a quiet place to pray. If it wasn't about poor personal rating or performance of the Master so what then was the reason causing the disciples to speculate about the leadership change?- death of a leader. The prophesised must have been very strong and substantial that made the disciples believed that it was going to happen to their Master? It became a scandal for the disciples when they heard Jesus spoke about his future's departure. They all got shock. There was a shock wave amongst them. After hearing Jesus predicting that
He would be delivered into the hands of men. They would put him to death and three days He will rise again. V.31
This was not the first time they heard about it. It was the second time within two days they heard about it. The Master was very serious about his death approaching in the near future. The disciples felt there was an urgent need to discuss about who would lead the group in case the absent of Jesus? They could not wait until they got to destination but discussed it urgently on the way. We don't know in detail what they would do without Jesus but their discussion seemed to indicate that they wouldn't disperse to go back to their former profession. No, they intended to bind themselves together as a group.
The disciples heard that their Master would rise again three days after death. Three days without the Master they probably could wait for Him to come back. The problem was firstly the concept of coming back to life from death was beyond their comprehension. Secondly they experienced the Master's concept of time was so much different from theirs. They heard Him talked about 'the hour' was coming and they have been waited for not weeks but months. Applying that concept of time for three days it must have lasted for years.
It is interesting to note that the Master was so calm, not angry when he heard the disciples discussed about the future leadership change. He kept quiet listening to them and when they arrived to the place where He intended them to be. He used the occasion to teach them a lesson about leadership. They need to be humble, servants of others and live to serve one another and growth in relationship to God the Father.