Current is not used up

The mistake

Assuming less current remains after each resistor in a series loop.

Why it feels right

Resistors 'use energy,' so they seem to consume current.

How to catch it

You draw shrinking current arrows around a one-loop series circuit.

The first principle

Charge is conserved. In a single series path, the same current passes through every element; resistors reduce electric potential energy per charge, not the amount of charge per second.

worked mini-example

Two bulbs are in series. Is current smaller after the first bulb?

Common wrong move

Yes, the first bulb uses some current.

Correct

No, the same current flows through both bulbs.

Test the repair CIR-05 · transfer
In one unbranched loop, 0.30 A enters a resistor. What current leaves it in steady state?

Make a fresh prediction before referring to the worked example.