[Gehinnn]

With dependency order you mean dependants before dependencies? (and dependencies lazily when they are requested again by the dependant)

If you update dependencies before dependants, the dependant might not depend on all it's dependencies anymore (because a derived might depend on A only if the observable B is true) and you do too much work/run into glitches.

[naasking]

Dependency order = values are computed in the same order as they would be in a purely pull-based system, which is intrinsically glitch-free

Push-based systems permit better efficiency and minimal state changes, but they should endeavour to preserve the above property for external observers.