Traders who have more experience may find this rule inappropriate, but for people new to bitcoin, this has done well over time.
That's a good lesson to learn; bitcoin is a tough market for new traders. Many didn't see the recent 12-15% dip coming and it did. Friday, I thought GBTC was cheap due to this oversell, just like I saw a lot of potential in GBTC before the bitcoin ETF was denied. It's a tough market though.
Having a strict rule - whatever it is, helps. For most people "3 percent" doesn't feel like a lot of risk. For some, it may be higher or lower.