What is the reason why criminal cases are always not heard in court? My friend was in prison for more than three months, and hired a lawyer, saying that the case was still going through the procedure

What is the reason why criminal cases are always not heard in court? My friend was in prison for more than three months, and hired a lawyer, saying that the case was still going through the procedure and there was no trial. Litigation has a time limit, but a long time is not necessarily a bad thing. There may be something wrong with the evidence, so don't worry. Let me show you two watches:

1, workflow in investigation stage

2, the first instance proceedings