Why did Norway join NATO, and why did its neighbors Sweden and Finland not?

Sweden is a neutral country and has always been an independent defense. Neutrality is not only a tradition, but also a profitable policy. Finland borders on Russian soldiers and has a lot of grievances in history. Recently, it was the Sufen War. Although Soviet Red Army soldiers were killed by Finnish snipers at that time, the resources and forces of the Soviet Union were too rich. Under such a brutal opponent, Finland's land and population are absolutely unsafe. Therefore, in addition to relying on the tradition of Finnish snipers to defend the country, the political strategy can only be to maintain relative opposition, find a balance between big countries and obtain security.