Based on the directly follows graph and the event log provided, here are some possible root causes for performance issues in the process:

1. High frequency of "Load Truck" events: The "Load Truck" event has the highest frequency of events for both Handling Unit and Container object types, with 10553 and 8559 occurrences respectively. This may indicate a bottleneck in the process, as the loading of trucks appears to be a frequent and time-consuming task. To address this issue, it may be helpful to investigate the causes of this high frequency and to identify ways to optimize the loading process.
2. Long duration of "Place in Stock" events: The "Place in Stock" event has a long average duration for Container object type, with an average of 743380.51 seconds (approximately 8.5 days). This may indicate that containers are spending a significant amount of time in storage before being loaded onto a vehicle. To address this issue, it may be helpful to investigate the causes of this long duration and to identify ways to reduce the time containers spend in storage.
3. High frequency of "Reschedule Container" events: The "Reschedule Container" event has a relatively high frequency for Container and Vehicle object types, with 36 and 25 occurrences respectively. This may indicate that there are issues with the scheduling of containers and vehicles, leading to the need for frequent rescheduling. To address this issue, it may be helpful to investigate the causes of these rescheduling events and to identify ways to improve the scheduling process.
4. Long duration of "Book Vehicles" events: The "Book Vehicles" event has a long average duration for Vehicle object type, with an average of 283101.01 seconds (approximately 3.26 days). This may indicate that there are delays in the process of booking vehicles, which can have a ripple effect on other parts of the process. To address this issue, it may be helpful to investigate the causes of these delays and to identify ways to streamline the vehicle booking process.
5. High frequency of repeated events for certain object types: For some object types, such as Truck and Vehicle, there are events that occur multiple times in a row (e.g., "Load Truck" -> "Load Truck" for Truck object type). This may indicate that there are inefficiencies in the process, as the same tasks are being repeated unnecessarily. To address this issue, it may be helpful to investigate the causes of these repeated events and to identify ways to eliminate unnecessary tasks.
6. Long duration of "Depart" events: The "Depart" event has a long average duration for Transport Document object type, with an average of 1007066.16 seconds (approximately 11.6 days). This may indicate that there are delays in the process of departing with containers, which can have a ripple effect on other parts of the process. To address this issue, it may be helpful to investigate the causes of these delays and to identify ways to streamline the departure process.
7. High frequency of "Depart" events with no preceding events: For Transport Document object type, there are 142 occurrences of the "Depart" event with no preceding events. This may indicate that there are issues with the tracking of events, as it is unclear what events led to the departure of these containers. To address this issue, it may be helpful to investigate the causes of these missing events and to improve the tracking and documentation of the process.
8. High frequency of "Reschedule Container" events following "Depart" events: For Transport Document object type, there are 21 occurrences of the "Reschedule Container" event following the "Depart" event. This may indicate that there are issues with the scheduling of containers, as containers are being rescheduled after they have already departed. To address this issue, it may be helpful to investigate the causes of these rescheduling events and to improve the scheduling process.