I have never left mine out all day so I don't know how well it would work.I am to paranoid about stuff happening.I can say I have always had dogs/puppies and about a month ago our then 7 month old lab mix just going out to play no more than 1/2 hour without being checked on or supervised he ate some sticks that caused blood in his stools enough to last a few days and make me worry ( and I don't panic easily about something when they are sick,I take precautions before) enough to go to the vet and 5 days of meds and he was fine but I worry if it had been all day unsupervised what he would do.He just goes out to go to the bathroom and play with the other puppies for a while and someone is almost always with them unless we are coming in for a drink or something quickly.There is also digging and I know if unsupervised digging out could someday happen, or a board pulled off the fence, even though it is 6 ft, wood,I check it every day,plus things can be thrown over the fence.,some people,sometimes who you least expect ,or kids can toss things over and can cause problems from mild to serious and my friends dogs did get their teeth caught in the collar of the other dog and blood was everywhere.It was terrifying.I can't imagine what would have happened if no one was there.I guess teeth would have been lost,or worse the other dog would have strangled.It is a hard decision to make and a scary one too.Good luck.I am lucky,I am home mostly and with our schedules someone is almost always here.
Laurie