As a gentle reminder, we're likely to have somewhere between two dozen and too many candidates running for president this election cycle. The odds of any one candidate securing a majority of pledged delegates are basically zero. This means that we're probably going to have a brokered convention, and this means that we're going to have to ask delegates who had been pledged to other candidates to support our candidate instead.
I understand that discussions can get heated, and that there are some candidates who people are fundamentally
opposed to, but burning bridges in a race like this is not necessarily a wise strategic decision. If I'm a Wayne Messam delegate, and I've just spent a year watching my candidate get attacked by Seth Moulton supporters, I'm probably not going to want to switch my vote to Seth Moulton at a brokered convention. On the other hand, if Tim Ryan supporters have always treated me with kindness and respect, I might be more inclined to vote for him, even if my views are more in line with Seth Moulton's.
Coalition building is an important part of politics. This is true in general, but it's especially true given the dynamics of this particular race.
Just a bit of food for thought.