Learn English – Word for delaying a decision with only one option

Single-use

adjective: single-use
1. designed to be used once and then disposed of or destroyed.
"billions of single-use cups are thrown into landfill sites every year"

The expression is also the de facto industry standard for that meaning.

ISO 15223: Medical Devices and EN 980 cite that single use instruments or devices be labelled as such on their packaging with a universally recognized symbol to denote "do not re-use," "single use," or "use only once". This symbol is the numeral 2, within a circle with a 45° line through it. (WP)

yardstick. dictionary.com

any standard of measurement or judgment: "Test scores are not the only yardstick of academic achievement."

As in:

Graduating from college shouldn't be the only yardstick telling whether a person will be successful.