Some processes have a long cycle of approvals which are delaying the final task execution. The delay is disturbing, while some people might miss an approval which restarts the process from the start. It complicates and delays execution dramatically.
The wrong part is that an approver has no any accountability on giving or not giving an approval.
The correct way to collect approvals is approvals by default. If an approver or substitute fails to review a task and give the approval within a pre-agreed period of time (1 BD is fine for most of the cases), the task is approved by default and the process moves forward. If any damage caused by giving approval by default, the approver who failed to review a task, assumes full accountability for the damage.
This way forces every an approver to be personally interested in giving the approval while keeping process execution quick.