At an extremely basic level, different people value various goods and services differently, so if I trade something that you value more for something that I value more, then we’re both better off.
Don’t forget inventions: in the long run, changing the set of available goods and services has been even more important (!) than improving their distribution. Notable post-WWII examples include high-yield cereal varieties, smallpox and polio vaccines, everything made with semiconductors and all the services they enable...
At an extremely basic level, different people value various goods and services differently, so if I trade something that you value more for something that I value more, then we’re both better off.
Don’t forget inventions: in the long run, changing the set of available goods and services has been even more important (!) than improving their distribution. Notable post-WWII examples include high-yield cereal varieties, smallpox and polio vaccines, everything made with semiconductors and all the services they enable...