system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How are software engineers objectively measured when problems span such large difficulty ranges and there are multiple ways to implement solutions?

Always been curious how "workload" is assigned and estimated for software engineers.
gpt
That's a problem no one has really solved yet.  
The way it usually works is that you break down big tasks in more manageable sub-tasks. Then you estimate how long each sub task is going to take, based on how long similiar sub-task took in the past, add up all the sub-tasks, then add some allowance for tasks taking longer than estimated, then add some more, and finally you have a number that you can tell your manager.  

If you have a team of people you generally know who works faster or slower and assign them a corresponding amount of work.

With a bit of experience it works reasonably well.