Whether you work in a public relations and marketing agency as I do, or you’re a firefighter or a CEO or an IT wiz, we’ve all planned special events. It may have been a wedding for 200 or a birthday party for six, but it’s still a special event.

In my two decades working in my field, I’ve organized and executed my fair share of special events. They’re a critical component to many public relations and marketing plans. They create new touch points, experiences and connections that just aren’t possible to communicate digitally or in a direct mail piece.

But, as anyone who’s ever put together a special event can tell you, there’s bound to be a hiccup. Or two. Or three. Or if you are really unlucky, maybe even a dozen of them. Thankfully, those hiccups are usually small, but sometimes they can be of DEFCON 1 proportions

So, here are a few fails I’ve encountered in special events. I hope as you’re planning your next special event, my fails might help you succeed.

1. Um, who checked the phone number? I worked with a delightful guy once who was coordinating a public event for a hospital service. He deftly maneuvered the politics of physicians, managed the budget, went round and round with red tape to get the direct mail piece finalized, and all went swimmingly.

Until it was discovered that the registration number for his event was listed as 800-555-0000, instead of 888-555-0000. And the number everyone was calling to register belonged, in fact, to an adult entertainment hotline.

Lesson learned: get someone with no relation to the project to double check whatever is going in the mail. They should call any phone numbers listed, send test emails to any email addresses given and visit websites listed.

2. Who said we only needed 5 volunteers? A CEO once wanted to thank the employees of the company I worked for (all 2,000 of us) and asked that each employee receive a pair of movie tickets and a Kudos granola bar in a gift bag. It fell to me to coordinate ordering the items, stuffing the bags and ensuring each person got their bag, no more and no less.

I calculated that we’d need a few volunteers, maybe five an hour for a couple of hours, to stuff these bags. To say I miscalculated would be a terrific understatement. The plastic bags were a bear to get open and keep open, the stickers we were using to seal the bags didn’t adhere well, and really we needed at least twice that many volunteers to make things move quickly.

Lesson learned: calculate how many volunteers you’ll think you need for the event, and add 30 percent. You can always divvy the work up more; it’s much harder to divvy up a too-small staff.

3. Who knew that’s what would happen to the balloons? A group of passionate employees I worked with long ago wanted to do something to mark a certain health awareness week that fell in the month of February. This particular instance was set up to be an epic fail, for a number of reasons: first, the employees were front-line clinicians and didn’t have a sense of audience, messaging, budget or tactics. Their intentions were wonderful, but their ideas were over-the-top and not likely to be noticed by many people. Second, I was alone in being the voice of doom and gloom, poking holes in all of their plans. They had the backing of senior officials, and the train they were on wasn’t going to stop.

So, on their own, they tied hundreds of ribbons to stakes, then attempted to drive those stakes into the ground outside of the hospital to prompt people to think about this particular health issue. The problem was that it was February, and the ground was frozen. And while THEY knew purple was the representative color for this particular disease, no one else did. So the few stakes they got into the ground left passers-by wondering what they were for.

But the bigger fail had to be the balloons. On the final day of the week, they wanted to do a balloon release in the hospital courtyard. Seemed innocent enough, until I pondered the logistics: how would these hundreds of balloons be delivered, already inflated? They’d be too big and cumbersome to fit into the elevators people used to access the hospital grounds, and potentially obtrusive in the hallways during delivery. And what about the hospital’s medical helicopter? It was parked directly above the courtyard, and if it needed to take off while all of these balloons were in air, what then? To say nothing of how it’s really not all that environmentally-friendly.

Somehow we figured out how to get the balloons delivered. And I called the helicopter coordinators, who arranged for the chopper to be flown offsite in case it was needed for an emergency during the event.

The day of the event was cold and grey, and a sparse crowd gathered in the chill for this little ceremony. Someone said a few words, and the balloons were released…only to find themselves stuck to the side of the hospital, sucked in by the air intake system. Hundreds of balloons, vibrating maniacally against the vents.

Lesson learned: Skip the balloon release. Plant a nice tree instead. But not in February.