Knowledge, signal, network

Every degree delivers some mix of three goods. Knowledge — you genuinely cannot practise medicine or structural engineering without it. Signal — a credential employers use to filter, which matters most in fields where the work is hard to sample. Network — the people you meet, which in some fields is quietly the largest component.

The mix differs enormously. A nursing degree is mostly knowledge. An MBA is mostly signal and network. Paying network prices for knowledge you could get elsewhere is the most common expensive mistake.