Is there a reason to open curtains if you are out of house during day light hours?

[Lasvegas]

I leave the house in the dark and come back when it is dark. Am wondering if I can save 5 minutes in the morning and not bother opening curtains. (not in the rooms where we have house plants obviously). Is there a reason to open them from a health or safety perspective for example?

Thanks

mossy!!!!!!!!!!!!!! [stern look]