.. it's when they are most relevant.
Take for example the current Bitcoin "drama" - I have read very good work done, arguing for and against Segwit, including by our very own 
I can not argue with Nathan's perspective because he's a very qualified critic, and I am not - however, I do not agree with this conclusions, and not only because he did not make a counter-argument 'in favor' of an alternative to Segwit.
Crisis / Opportunity
You have heard the saying that the kanji for "Crisis" also contains the character for "Opportunity", in Japanese .. it has never been more true today in crypto. But what motivates those taking positions ..
The Legit Opposer
They truly believe that there are problems with that which they oppose - with recognition for the strengths of that which they oppose.
The Legit Supporter
They truly believe that the technology they are promoting is the better option - with recognition of the strengths of alternatives.
The Self-Interested Bullshitter
They simply wish to see that which oppose ruined and removed from the marketplace, for any number of reasons - for example: investing in, or belonging to a development team working on a competing technology.
The Fool
Keep in mind that the person taking a position for or against, may be simply confused and are entirely wrong in their assumptions, and they know too little about the thing to know it .. they are taking this side or that side simply because they wish to participate in the debate, and hopefully end up on the winning side.
Back to Segwit ..
Folks, I am here to say that it absolutely does not matter whether or not "Segwit" is the better solution, when it comes to increasing Bitcoin speed and performance. What matters, is that the majority of those maintaining the Bitcoin network believes it to be, or that they have decided to follow those who do believe it to be. The goal should be singular, to avoid a fork that would create a different flavor of Bitcoin, which will greatly diminish the stature of Bitcoin, which all crypto investors and enthusiasts should hope to avoid.
Do not listen to "The Experts" sowing discontent and disarray ..
.. it may be their bread-n-butter, but for the rest of us it could literally mean "Disaster" .. in the English sense of the word, which simply means .. DISASTER!
Just Keep it Simple ..
.. whichever one becomes "Bitcoin" .. or remains "Bitcoin" .. or whatever ... not Bitcoin Cash .. Bitcoin Classic .. Bitcoin Not-Going-to-Be-Around-Very Long ... just str8up "BITCOIN!" The one that is currently worth nearly $ 3000 US smakaroonies, and will only go up from here.