Dressing according to the weather climate or waiting until the Weather Breaks?

Tweet

The weather is slowly breaking, day by day, but it's in the 30's some days then the next day can go up to the 50's-60's then go back down again... Around where I live, I've seen so many people dress for the weather, if we have a pretty good day high 50's, I see people with tank tops on, shorts, sandals...The next day the weather gets cold and they back to pants, boots etc.. Now the way I'm thinking is that person could catch a cold. I think I'm going to catch or cold, me doing that. But, I see so many people do it and they say they are fine..Some do catch colds, but work on the cold and don't mind it...That amazes me... There is this guy at my job who wears shorts YEAR round...I think I saw him with pants on twice this year and it's gotten really cold here. He will come to work when it's 15 degrees outside. I ask him all the time isn't he cold and he says no...I guess he hasn't caught a cold because his body is use to it, I don't know... So my question to you is, do you dress day to day as the weather climate changes or do you continue to wear your the same clothes until the weather changes where there is more consistency? Why do people do that knowing it's possible they may get sick?