The phrase "countless occasions" means that something has happened or can happen a lot of times, but there are too many instances to be able to count or keep track of. Full definition
In turn, he has the experience and pedigree to deliver on the big stages and has shown on countless occasions how his tactical qualities can make the difference. (caughtoffside.com)
I have made these rolls for countless occasions and they are a big hit every time. (whatmegansmaking.com)
There have been countless occasions when I needed to carry more than one child, but have always needed to use 2 separate carriers. (clothdiapergeek.com)