History
Vanguard introduced LifeStrategy funds in the 1990s as a direct extension of John Bogle's indexing philosophy. These funds package global stocks and bonds into fixed allocations (e.g. 20/80, 40/60, 60/40, 80/20) and rebalance automatically. They became one of the most widely used entry points into passive investing globally.
Philosophy
Keep allocation fixed, diversified and low-cost. The investor selects risk level once and delegates all future decisions. It is designed for discipline and simplicity rather than optimization.