The second time you install vacuum tubes into a handmade 2A3 stereo amplifier, you’ll know that two of the four pins are slightly larger than the other two. And you’ll know that the tubes go in pretty easily, you don’t have to force them.
You may know these things because the first time you did it, you pushed really hard and wrecked the tube.
Experience has easily measured value. If it’s important, don’t hire a rookie.
