Why in WW1 or WW2 or ever nobody invaded Switzerland? All other countries was in some wars. How Switzerland do it and should we learn from them?
I hear that many people with power have money in swiss banks, is that factor or not?
Simply because Switzerland was a worse alternative plan strategically than Netherlands and Belgium.
Hitler had a plan to attack Switzerland, named Operation Tannenbaum but the Maginot line could be breached through Belgium and Netherland. So it became needless conflict with no gain.
It is a less known fact that Switzerland (German part namely) was part of the Greater Reich Hitler dreamt of. He wanted to merge all Germanic territories under his control, but for strategic reasons he simply gave up on that. I am sure the logic behind it was: if Germany wins the war, Switzerland will have no choice, but to merge into the unified German Reich. So Hitler didn't have to waste resources on Switzerland, Operation Tannenbaum was about getting access point to France, a lot better one than through Maginot line.
Switzerland isn't much of a "prize." It has about 16,000 square miles, and about 4.5 million people in 1940 making it twice the size of New Jersey, with about as many people. http://en.wikipedia.org/wiki/Switzerland On both counts, it is one of the smaller countries in Europe, and less worth having.
On the other hand, Switzerland maintains a policy of armed neutrality. EVERY MAN (except those blind or crippled) has served a year or two in the army, and possesses a weapon. They mobilized 850000 men in 2nd world war as preparation according to WHKMLA source. About two thirds of the country is mountainous, and it can get quite cold in the wintertime, making it good for defense.
Also, Switzerland was very convenient as a "clearing house" for (both sides), in banking, but also in espionage and prisoner exchanges.
Basically, Switzerland was worth more to the Germans neutral than what it would have cost to subjugate her.