The short answer for a Sheltie household
Yes. A Shetland Sheepdog will usually bark more than most breeds, and it is not a training failure or a stubborn streak. Shelties were developed on small, windswept farms to move and gather sheep, and a herding dog that works at a distance needs a voice its handler can hear across a field. That working voice came home with the breed. In a house it gets aimed at the post arriving, children racing past on scooters, a neighbour's gate clicking, or simply the excitement of you picking up a lead. Most Shelties are not barking to be difficult; they are reporting, enthusiastically and in detail, on a world they notice more keenly than calmer breeds do.
Why this particular breed notices everything
Three Sheltie traits stack on top of each other. The first is alertness: a good herding dog watches movement constantly, so a Sheltie clocking a cyclist through a gap in the blinds is doing the observational part of its old job. The second is sensitivity. Shelties read tone, routine changes and household tension quickly, and a dog that notices a raised voice or a suitcase by the door often vocalises that unease. The third is intelligence without an outlet. A bored Sheltie left to patrol windows all day will rehearse alert barking until it becomes the default response to almost any sound, and rehearsed barking is much harder to soften than occasional barking. Noise sensitivity matters too; some Shelties react to high or sudden sounds that a less reactive dog would sleep through.
Living with the noise without fighting the dog
Shouting over a barking Sheltie rarely works, because from the dog's side of the conversation you have simply joined in. What works better is a sequence the whole household uses the same way. Let the dog give one or two alert barks, name what it saw in a calm voice, call it away from the window or door, and reward the moment it turns to you and goes quiet. Practise that quiet cue separately, in boring moments first, pairing the word with a treat delivered during silence rather than during noise. Meet the breed's needs earlier in the day: a Sheltie that has had a proper walk, some scent games in the garden and a short training session has far less leftover energy to spend on commentary. If your dog fixates on the front window, limiting access to that lookout during the busiest part of the day removes hours of free rehearsal.
When Sheltie barking is telling you something else
A Sheltie whose barking suddenly escalates deserves a closer look rather than more training. Barking that arrives with pacing, panting, drooling or destruction when the house empties points towards separation distress, which responds to a gradual alone-time plan and, if it is not improving, a conversation with your veterinarian about anxiety. Barking that starts in an older Sheltie, especially alongside restlessness at night or confusion in familiar rooms, is worth a veterinary check rather than an assumption that the dog has become naughty with age. Pain can also lower a sensitive breed's tolerance for noise and handling, so a marked change in a previously settled dog is a health flag first and a behaviour question second.
A realistic expectation to set
You will not, and should not try to, train a Sheltie into a silent dog. The honest goal is a dog that alerts, checks in with you, and settles, instead of one that barks in long, self-rewarding chains at every passer-by. Most families reach that middle ground within a few consistent weeks, and visitors usually find a quick alert bark followed by a dog trotting away far easier than the non-stop version. Keeping the routine consistent is where KinsLe helps most, because Care Teams in KinsLe let you assign the morning exercise, the window-management habit and the quiet-cue practice to different family members so your Sheltie hears one clear message from everyone.