Conclusion
Curved window bars are not necessarily just a strange architectural detail.
Depending on the building, they may provide security, create additional outdoor space, support plants, or add a decorative element to the window.
There is no single explanation that applies to every curved window grille.
The next time you notice a window with bars that curve outward at the bottom, take a closer look. What appears to be a simple decorative feature may actually be the result of several practical design considerations working together.
