I often answer if its unknown (a few family members like to set their numbers to unknown for work reasons). I should really stop answering even if Truecaller doesn't identify them as a scam.
Don't be like me. I didn't realise I left my garage door open all day. Thankfully no humans entered or stole anything but a neighbourhood cat got in and didn't leave until 2 days later.
I prefer going in on Fridays, the commute is faster and I often have something on after work thats closer to the office than my home.