People who make flippant remarks on MN about "train your bloody dog" often fail to appreciate that there is an inbetween stage where the dog is learning but isn't yet the finished product - and sometimes that dog will forget everything it has been taught about manners and make a mistake - particularly in the teenage months but sometimes at other times too.
Sometimes that dog has come into a rescue as an adult with no training, or even some behavioural issues. Please don't assume that the person holding the lead is the cause of the issue, or that they're not trying to solve it. You don't flick a switch and get a perfect dog, and some of us are doing dog ownership on hard mode.
My dog's specific trigger is motorbikes - and there are many in our part of London and we can't leave the house without seeing one (alas, I gather it's considered disproportionate to ban Deliveroo and Just Eat from operating just because they happen to be the bane of my life). He's perfect in the park, he's perfect in the house, but the street is tricky.
If you see my diving into a driveway to avoid a motorbike and clutching an open tube of Primula cheese, it's because I'm training him, not acting like your neighbourhood weirdo. If you see him barking on the street, please appreciate that there is NOTHING I can do about it until the motorbike leaves, because he's essentially having a meltdown and is past the point of no return. I'm not not training him, I'm just not fighting a battle that has already been lost.
The sheer level of judgement that I've had from clueless members of the public is something to behold. They have no idea what he has been through or how he was failed in the past. They have no idea how much he's improved. They have no idea about how much time, effort and money has gone into fixing him. But they still see fit to tut and make snide comments about both me and my dog. Truly, it is like being the parent of a special needs child who is prone to public meltdowns.