Sometimes, not as often as when I first started cake decorating, my butter cream doesn't want to stick to the cake. While I am covering a cake and I run my spatula over BC I just put on the cake, a section will stick to the spatula and comes right off the cake & the cake looks like there was nothing ever covering it. I'm just wondering if it's the way I am putting it on sometimes (since it happens less and less the more I cover cakes) or if there's something I can change so this won't happen.

it sounds like your buttercream is too stiff. Trying thinning it out.

What is the recipe you used for your buttercream?

If it's too stiff, why does it only happen occasionally? I make it the same pretty much every time.

I have two recipes that I mainly use, one is all shortening with butter flavor added. But I remember this happening when I was a kid and would try to frost a cake with a can of store bought frosting.

Do you wrap your cakes after they come out of the oven.

When I bake one night and don't plan to do anything with the cake I will wrap it in plastic wrap. Sometimes while the outside of the cake may feel cool the inside is still a little warm and I have found this gives me a very moist cake. And icing doesn't always like to stick to really moist cakes. So if I feel like the cake is too moist, I'll just let it sit out in the air for 10 to 15 mins to help dry the outside a little bit.

Not sure if that is your issues, but the two things I have found that cause issues with icing not sticking is the icing being too thick or the cake being to wet/moist.

Do you crumb coat your cakes first?

TexasSugar, I bet that's it! I like to tort/level/sculpt... and crumb coat the cake ASAP when it comes out of the freezer. (I wrap in cling wrap and then foil.) I bet it's the one's that I don't get to right away or take more time on leveling and such. Once they start thawing they do get more moist on the outside. If this happens again, I will let it sit like you said, and dry a bit. Thanks, girl!

If the cakes are thawing unwrapped or after the crumb coat it is likely there is condensation on the outsides of them.

I don't freeze cause I just don't have the room, and I pretty much don't put anything in the fridge because it is very humid where I am, so then I'd have to deal with the condensation.

Good luck on your next one.