Actually confidence is a tool while many failed and some too with hood confidence overcome the force of selling off their holding, but there is one aspect I do consider while most holders sell off their Bitcoin the area of unforseen circumstances and loss of target over speculated period of time, some holder have some speculation while they hold that certain period what they are holding should be at a certain price and when the reverse become the case and their alternative failed them they are left with no option than to sell what they have. Though it's very wrong shall but to say when the need is not available the available become the need could be their situation at that point because some is not as a result of clear eye but been instigated by unknown factor beyond some emergency fund mostly life threatening issued.
An important aspect is discipline and I think this is what you are trying to point out, it is a quality that every investor needs to have to be a successful bitcoin holder because the journey is not always rosy and it will take a strong mind to withstand and overcome the selling pressure when there is a dip in price during bear season. A disciplined mind will achieve a whole lot over a long period of time with bitcoin, there is no need to panic and sell when things are not going well you just have to keep in mind that there will be ups and downs during the journey.
To avoid selling we need to strategize and plan our investment properly and not invest money we intend to use for other things and we should always set aside emergency funds to cater for unexpected expenses to avoid liquidating assets prematurely but most investors take it for granted and feel it’s not a necessity.
Your point per discipline is inevitable when it comes to investment in general mostly the most valuable like that if Bitcoin, but my point of argument or opinion remain that if what emergency fund can't not resolve because there is not amount of fund that can take care of unforseen circumstances like life threatening, if you have not seen heavy investors hit with life threatening who sold their properties and many belongings even seek public contribution inorder to save their life I I have witnessed even hear some through news or Media sorry to use this common example of a Nigeria actor who was hit with illness that leads to amputation of his leg the man called john okafor popularly known as Mr ibu , the public made some donation and he lost his life if such a person has Bitcoin as asset and selling it could save his life you think he will reserve it and died because of long time holding, when I said life threatening it really entails life issue with deep sense of details. Sorry to use the particular scenario assuming a man kept emergency fund that is not up to what a kidnapper who adopted him is looking for and no means to get the demand, you mean such person should die and leave the Bitcoin unsold if he practice Long holding where means of selling and get released can be made, for me it's unwise.