The OP is entitled to his opinion (whatever it may be), but as others have already written, I can only repeat that it is a really bad idea to "convince" someone in any way that they should invest in Bitcoin, and that's just for reasons that one day he would profit when he sells at a higher price. With such an approach, we turn Bitcoin into some kind of get-rich-quick scheme, and not what it actually exists for.
If you are already telling someone about Bitcoin, then at least start from trying to get people interested in trying to use BTC as a currency, and how to learn to be their own bank. Someone who shows no interest in these things should probably not buy BTC at all, although everyone does what they want with their money.
Sharing your knowledge indeed is different from persuading someone; has something to do with the consequences. As we all know, we have different perspectives on a particular subject. To us, investing is beneficial in the long run and others might as well think the same way but it would vary on how we measure or manage the risk. Some will just be too hopeful of the profit and often disregarding the risk. Profit won't come in an instant. Ofcourse it would be easy to say "just hold it for years" even if we are having different circumstances. Not all would be able to do so which simply means not all investors would be earning huge. Some would be even be in huge loss. So what's the point? Give them freedom and time to take the initiative to engage in this industry; in such way they'd be more responsible and aware of how things work for this industry.
Its important and right to tell the difference between sharing information and trying to change someone's mind. Investment is not a one-size-fits-all method. It's a dance of numbers and feelings, a dynamic interaction between risk and return.
Even though Bitcoin is amazing, it is not an exception to this rule. "Hold for years" is not always a good way to solve a problem. Each investor has a unique set of situations, financial goals, and willingness to take on risk. The risk comes from reducing this complicated story to a single piece of advice - to hold. Some people will find gold, but others might get stuck in mud.
The key isnt to tell people what to do, but to give them information. Let them make their own way. Its not enough to just let them learn about Bitcoin; they also need to be ready for the trip. Equip, but dont lead.