You go because your dog needs to run and needs dog friends. You come home having shouted their name 15 times and collected them by the harness.
We are not going to moralise about this. Some dogs do fine at a park. For many adolescents, an hour in a busy one is the worst hour of their week.
What a busy park rehearses
Responsiveness to a caregiver's cues drops around the onset of adolescence and returns later in the stage. A park full of dogs is where that dip gets 45 minutes of practice.
Learning near a trigger depends on working below the threshold at which your dog reacts. A gate, 12 strange dogs and a tennis ball is above that line for most adolescents.
Our reading is that a few bad encounters also bank. A dog who has been mobbed or told off hard at 11 months old can carry that into how they meet the next stranger.
The park is also where owners end up grabbing, shouting and telling a dog off. Punishment-based approaches are associated with fear, avoidance and defensive aggression, and the gate is a poor place to find that out.
The honest test
Answer these about the last 3 visits, not about the dog you are hoping for.
Does your dog come back to you mid-play, at least 1 time in 3, without you walking in?
Can they take a 30 second break beside you and stop staring at the other dog?
Do they leave a dog who has said no, meaning a dog who turned away, curled a lip or moved off?
Can they still take food inside the gate? A dog who will not eat is over their limit.
Do you leave calmer than you arrived, or having lost 3 things you were working on?
Mostly no is a clear answer, and it is a pause rather than a verdict for life. Plenty of dogs come back to parks at 2 years old and are unrecognisable.
Better places to practise this month
1 calm known adult dog, walked alongside yours, rather than a free-for-all with strangers.
The same park at 7am on a Tuesday, for 10 minutes, when there are 2 dogs in it rather than 20.
A quiet field or path with a 30 foot long line, so running off stops being rehearsed.
A walk with a friend and their dog, side by side. Walking together builds more than wrestling does at this age.
If you do keep going, the behaviour inside the park is its own job. Mobbing, humping and greetings with no brakes have their own article, and that is where the instructions live.
Safety note
Stop going for now if your dog has been in a fight, has been bitten, or plants at the gate and will not go in. Sudden behaviour change warrants a veterinary examination. New growling, snapping or fear of other dogs needs a qualified behaviour professional rather than more park visits.
Today's version, in one line: score the last 3 visits against the 5 questions, and pick 1 quiet alternative for tomorrow.