I travel a lot. And by a lot I mean a new passport per year because all the pages are stamped or filled with visas.
A couple of times I have been asked more questions than others at several borders because my history seems false, while its completely true. What happens if the first officer I met in a border doesn't believe me? Will they deport me or deny me entrance right there or is there a secondary questioning somewhere else?
I always have a flight back home, money, credit cards and insurance plus the correct visa for business, but I want to know if I will have a chance to prove I'm not lying or if I will depend solely on one person's opinion.
Some context: I'm a 26 year old software evangelist and you can easily see that online with photos and videos plus I usually bring with me conference material with my name on it (it actually saved me once at Barajas airport)
Edit: I also travel for pleasure and the worst situation I experienced in a border and made me ask this was while I was in between conferences and entering a country actually for tourism before departing to another event. So this is a general question and not about public speaking while traveling.