I think there could be a better example for what Xeylode is asking. What if you don't know that the counter will hit, but it looks like there's a good chance it will (not quite guarenteed, but the follow-up would be easy and would probably mean you get the kill), but something more like running off the edge->fair look like it has a decent chance of succeeding, but failing means you will most likely die. At least I think that is what he is asking.
This is basically all risk vs reward and also how well you calculate your chances. There is also the case where you NEED to get this edgeguard in order to make up for a rather bad deficit (lets say fox is at like 20%, but is 1 stock ahead of you). In that case, taking the riskier option might be your best bet at winning the match. If you think you can pull off the more dangerous maneuver, then it is most likely worth it imo. The main thing is if you are confident with the maneuver. This is where practice and familiarisation are very important. It should only fail if your judgement was wrong, and your judgement should be correct as often as possible. If you drop it due to execution, you need to practice more. In friendlies, I almost always go for the risky option if I don't know what will happen. This way, I can better judge the situation in the future, but also, I will have the practice for executing the harder option for when it really matters.
Getting back to my point, you should know which option is better. You should know, more of the time, when the counter will not work, so that you can remove that option sooner and allow you to evaluate your other options better. Similarly, you should know, at least more of the time, when doing a risky maneuver will and won't work. If it comes to a crucial point in an important match, you don't want to be guessing or taking unnecessary risks.