I always say, "**** happens". If the seller have live guarantee, you usually don't have to worry about it. It's times when you actually buy a $10 fish and pay $50 shipping, considering that most guarantees only cover the cost of the fish, you're in for a loss. That's why I usually make orders over or equal to the shipping rate.
Another thing is, always buy from reputable sellers. When you don't, the seller ships you a sick fish that arrives in bad shape (but it's still alive) and dies a day or two later. That's your loss 100%. Good sellers (especially if you're a return customer) will give you some kind of reimbursement (in one way or another) if that happens, especially if that seller has "healthy fish" guarantees also.
Another thing is, always buy from reputable sellers. When you don't, the seller ships you a sick fish that arrives in bad shape (but it's still alive) and dies a day or two later. That's your loss 100%. Good sellers (especially if you're a return customer) will give you some kind of reimbursement (in one way or another) if that happens, especially if that seller has "healthy fish" guarantees also.