In a negative feedback op-amp configuration, what is the primary reason for implementing feedback?

In a negative‑feedback op‑amp, the main reason to add feedback is to make the amplifier behave predictably and linearly, rather than letting its internal transistor variations dictate the output. The feedback forces the amplifier’s input and output to satisfy a simple equation that depends only on external resistors, giving a stable, known gain. This stabilizes the gain, reduces distortion, and limits the effect of temperature or device‑to‑device differences. As a result, the circuit’s behavior is determined by the chosen resistor values, not by the op‑amp’s internal parameters. For example, connecting a resistor from the output to the inverting input forces the op‑amp to adjust its output until the voltage difference at the inputs is zero, ensuring a precise 10× gain.