Please describe fatigue

Please if you could describe what fatigue feels like to you. That way us newbie can tell when we reach it. So far my idea of fatigue is just when your penis can’t take anymore yet I have no clue what that means. Is it like your penis is sore? I know pain is bad but tell me what fatigue feels like to you.

Extreme discomfort (not terrible). Many hangers don’t experience fatigue until higher weights so don’t push it. I jumped up 2.5 pounds to hit fatigue and my erections have been suffering lately so I’m taking a break. Looks like I needed more conditioning.