This can be a touchy subject for some people. Some feel it is cruel to crate a dog, especially for an entire workday. But here is the thing. Dogs are naturally den animals. By crate training the correct way, you are providing a safe and calm space for your puppy/dog to sleep and relax. For puppies this is especially important because as we all know they can and will get into anything and everything. So by putting them somewhere safe when you can not supervise them, you are keeping them safe. We have all had that moment when we step away for just a few seconds or mins, pup was occupied with something and took the opportunity to step away and came back to a disaster.
I learned the value of crate training many years ago. I had a puppy who never got into anything, so I didn't crate train her. Then one day I had a doctor's appointment and was gone longer than usual. When I returned home I found the mattress to the futon pulled off the frame, the pillows off my bed unstuffed, the sheets ripped off and the trash all over the house. She was six months old. I promptly went out and bought a crate. There started our crate training journey. We went slow and I kept it positive. I had never heard the term crate games before, but we played them. Within a short time she loved her crate and would choose to go in for naps all on her own. The door stayed open and she was free to come and go. I will say this though. One time, after a move I had to go to an appointment and while I was gone she ate a corner of her crate. Well, chewed through it. She had been crate trained for over a year at that point and it wasn't something I expected. But with all the big changes in her life, she was stressed. It was her first day in her new home and I had to leave her. That didn't change her love of her crate, it was just how she delt with a stressful situation under less than ideal situations. Once we settled into that home, she no longer had the door closed when I left. Yet she still went into it each time I left on her own accord. It was her den. Her safe space.
Crate training is important for a wide variety of reasons. If your dog ever needs to have a stay at the vet, they will be crated. If they are ever injured and require crate rest, their stress levels will be significantly reduced if they are already comfortable in a crate. It is important though that a crate never be used as punishment. It should be a positive place for them. Take your time during the process and if you run into any issues, seek out the help of a trainer. It is a lot easier to correct a problem early on than to fix what could be a major issue later on.