Say you decide to get away for the winter, so you book a flight using miles and head to Melbourne for a month.
In theory, say when you get there you’re amazed by how sunny it is. Say you start spending all your free time out in the sun as much as possible.
Suppose, by some stretch of the imagination, that Melbourne faces extreme UV levels in the summer. And say in theory you like to walk long distances, and do so daily.
Say you hate traveling with a heavy load, so you – in this 100% fictitious story – don’t always pack water for your outings.
Say you coat yourself in SPF 50 regularly; and let’s just say, for the fun of it, that you consider this to be ample protection from the elements.
In the previous, totally hypothetical scenario, you would be an idiot. Because you would get sunstroke.