There are many things which can be looked under this phrase and many things do exist that work under the this phrase. Have you ever heard of the "Law Of Pre-Emptive Strike" ? It definitely falls in the category of precaution. You see this is the law on which the Iraq war, the Afghanistan war and many other small scale U.N and American wars are based, outside their Territory. The law means that you attack someone if you see them as a security threat even before they strike you. This is a clear image of precaution taken internationally. Now this is a BROADER SPECTRUM of looking at the phrase "Precaution is Better than Cure".
This example was one of the Heavy Weights of this phrase. There are many small things we see in our daily lives which though unconsciously, fall in the category as well. For example the Home builders and planners try to use the best material for the house. The reason is simple, the house stays durable for a much longer period. so instead of waiting for it to get sick and then try to cure it, they take precautions. There are many other examples which we face everyday. Using helmets and knee guards etc...
So this does prove that it is not just not a matter of medicine and sickness, but the phrase is applied and can be applied in our lives. Both in the ups like big decisions, and lows which are our normal routine decisions. Like ironing your office or school clothes before going to sleep or polishing your shoes so that you have them ready in the morning, so that you don't have to think of any excuses to the headmaster. There are many things that can be done so always remember "PRECAUTION IS BETTER THAN CURE".
