Whether investing in bitcoin is a risk or an opportunity, it all depends on each investor's knowledge and investment strategy.
Knowledge, strategy you say not a bad pointer but I would prefer to use the word "Investors Fate".
An investor who really cares and wants a solid Bitcoin portfolio will do anything within his power to consistently invest, and incorporate positive habits to propel him as he accumulates Bitcoin. In a simpler term, Investors need to have a plan, Target, strategy, Amount readily available of which they must be consistent, discipline about using this tools to create a good track for there Bitcoin holdings.
As I would always say, depends on how valuable you view Bitcoin to be, that is what will be the trigger.
Most people have plan , target but at the end they will endup selling their bitcoin very early. The reason is that most of them don't actually have trust and patience when it comes to investing in bitcoin. The moment one trust in Bitcoin and believe that Bitcoin ain't gonna let him down he or she have already started in a good way . Like for instance back then the reasons I normally sell in losses where due to fear that whenever a dip occurs it may not rise back , due to the knowledge I have Back then but now when am holding I don't show any fear , most time when there's dip I just focus in accumulating more because I believe it's Bitcoin and it's going to surge more .