Defence conferences are particularly challenging as speaker dropout rates are especially high because of the nature of the beast - if an officer is moved to a different assignment, there is no guarantee that you will get his or her replacement and if he or she is ordered to do something else that week by senior command at the last minute, your conference understandably comes second. Additionally, with reduced budgets, the military are increasingly struggling to attend conferences which poses challenges. The issue for the producer is that you are very much judged on the event you ultimately produce rather than what is on paper. Naturally, some producers are better than others and source replacements when a dropout occurs but sometimes you can still be very unlucky. An event rarely takes place where there isn't at least one dropout which wasn't salvaged. You are then judged both internally (by the sales team) and externally (by the industry sponsors) who are wondering why the person they were there to meet hasn't shown up.
In terms of the company itself, there can be a tendency to push ideas for conferences for the sake of getting an event into the market at a given time of the financial year. I am all for trying new concepts and I do realise that, as a business, there are certain budgetary targets that have to be met. However, sometimes you can be given a topic which you know is going to tank and the blame for it going wrong will probably rest with you.
To the company's credit, they do emphasise topic generation to enable new ideas to come through. However, if you are managing let's say 5 or 6 events, the last thing you want to do when you are under pressure is have to do research for another meeting. This is certainly all part of time management but sometimes there isn't enough time in the day, particularly if you prioritise doing the unsaid things that make a good producer (i.e. putting time in with each of your project teams).
Ultimately, your enjoyment at IQPC will depend on your relationship with your immediate manager as he or she reviews your performance to senior management. I was lucky and had an excellent boss who trusted me to do the job, backed me when I was taking a risk, and still supported me if an idea of mine didn't pay off.