When we are in the corporate world it is normal to stay up late to finish our work in order to meet the deadliest deadline. Every workplace has its own culture on how to manage overtime and late schedules in work, but in our case since we are an NGO, we don't have any definite time-in and time-out, as long as you consume the official eight (8) working hours.
Overtime is normal if is consistent, but what are the things that we should do to avoid it or how can we make our workload manageable. I think overtime is a product of inefficiency and disorganization of tasks and responsibilities. Some people will request for an overtime is there are things urgent, but you can gradually do that thing beforehand to avoid cramming.
Sometimes the one who instructed you to do that work, do not understand what he has instructed you because he crams and just instruct you to do this and do that without even thinking if it is feasible or not. Well, I understand the position of the bosses because they have a bigger responsibility in the organization and everything you do, reflects their management.
In the end, the big bosses will blame your direct supervisor if something goes wrong and your boss will be the one to relay it to you. In short, your direct boss has much pressure than you. I understand every boss, its not easy handling people. Its up to the management of each organization to make a policy with proper implementation.