Most people do take a long time to explore the country thoroughly, if they ever do it.
I'm probably the odd one out, as during my first holiday of 3 weeks I visited, in order, Bangkok, Yala, Chiang Rai and Pattaya, with some one night stopovers in Chiang Mai and Bangkok in between. If Bangkok wasn't enough of a culture and temperature shock already, can you imagine what visiting Yala after a 20 hour train ride felt like?