Bitcoin investment is too volatile for a person to monitor with an uncertain mindset, this could lead to the person selling their bitcoin at a time when the market value is low out of the fear of losing out and this can/will ultimately lead to them losing out when the price skyrockets.
When the price skyrockets isn't a time to take profits if your accumulation target has not been reached, remember Bitcoin is an investment for a long-term and targeting the bull run as a benchmark for success or harvesting is trading and not necessarily investment. I think they would lose out instead to get Bitcoin at a cheaper price, even if the price skyrockets, there's still a chance to accumulate at the point they decide to get actionable, but the good prices are lost and they would get lesser quantities for same amounts compared to bigger quantities they would've got at a cheaper price of they've started now to take action and embark on their accumulation journey.
Funny enough they may become redundant to take action when it's obvious to them that they failed in their gambling with Bitcoin price and may entirely miss out investing into Bitcoin. Waiting is detrimental, but being actionable in your Bitcoin involvement is the key to success in Bitcoin.