Visitor Visa - B2

I applied for B1/B2 visa at US Embassy Riyadh. Completed DS160 online, paid my visa SR608 at SAMBA, bring documents during my interview (DS160 confirmation page, SAMBA receipt, employment letter, photo, bank statement, appointment confirmation, travel insurance, flight booking, old & new passports, exit/reentry visa, copy of iqama).
the interview:
Me: good morning how are you today! (with a smile), note: I greeted the Visa officer first
VO: im good, and u?
Me: im good as well
Then the VO scanned my passport and DS160, quickly read my employment letter and the first page of my bank statement.
VO: so why would you like to go the USA
Me: for toursim and I wanna visit a friend of mine who used to work here in KSA but now he's there
VO: ok thank you!
Me: (then i waited for the next question after few seconds) that's all?
VO: yes! thank you (gesturing me that the interview is finish)
Me: ah OK thank you!
then after 3 days i received an sms from Aramex saying that my passport is ready for collection, when i opened my passport the B1/B2 visa is there valid for 10 years, I was so happy ;-))