Did you ever think about the workday? 9-5, they typically say, even though there's generally an additional half-hour to an hour included for lunch, which changes things around a bit.
Now think about the things that can cause variation in this schedule. There are places where work has to continue 24 hours per day, so that people come in in shifts. There are places which have a lot of connections in a different time zone, so they shift their daily schedule earlier or later to have better rapport with the other location(s). There are places where the lunch hour is extra long to accommodate the main meal at noon, or the main meal plus a nap (potentially).
Of course, it wasn't always an eight-hour day. Historically, people used to work brutal hours - fourteen hours a day, etc.
Humans have the ability to keep working for long periods of time. This makes sense given our size, our warm-bloodedness, etc. We have our ebb moments, which are ideal for siesta time.
What might change that?
I look around at the animals of the world for inspiration. Tiny mammals like mice tend to have very high energy for short periods of time, and then flop down for a rest, and then go back at it. Cats have incredibly high intensity sometimes, but sleep a lot. Some animals have stamina for hours, and some don't.
This is useful to consider, because for whatever world you're creating, it's good to consider how they organize their daily time. Especially if you're dealing with aliens, it might be useful to ask yourself how their energy levels translate into work patterns. The difference between a nocturnal creature and a diurnal creature is obvious, but there are more subtle things you can do to make a big difference.
As my friend Janice recently asked me when I was working on something for my otter story, "These are otters. Why would they sit while working?"
It was a wake-up question. I'd recently seen a video of a baby otter playing with toys in someone's home, and one of the things the film said was that the human was a specialist working with the otter while it was out of its natural enclosure - not someone keeping the thing for a pet. If you'd seen the energy of this thing, you'd see why. It would get bored one day and tear your house apart.
Mind you, my aliens are big, and this tends to change metabolic rates (whales and elephants move more slowly than rats and mice!). However, I figure they could still be on the otter side of the metabolic pattern relative to humans, and come across as very energetic.
It changed the way I thought about the organization of their days, and also about the organization of their work spaces, and all kinds of things.
I encourage you to consider this if you're doing something similar.