Compared the two options below.

I think the manufacturing cost is 100 times different but durability is not 100 times different.

— SGD 10+ Naitonal battery-powered shaver can last a year

— cheapest disposable 10-pack for SGD 1.05. Each shaver can last about 1->2-3 weeks. (I shave about 100 times a year.) So 25 disposables/Y i.e. below $3/Y

Tip: tooth brush can double its durability.

Durability declines more gradually, whereas the electric shaver would stop working completely.

Also, easy to carry.

Light weight. No battery.

I often need one in office (lasting 2->3-5 months)