The public events are great and I've been in quite a few now, but I have found a few issues 1.Sometimes I will be on my own exploring and one will appear, this means I have to tackle them on my own which is often impossible to complete. 2.There may be five people in a single area for a substantial amount of time but no public events occur. This can be especially annoying when bounties require you to finish three public events gold.
Ok my friend that seems logical at least for the second but the first, you are not obligated to complete a public event it's not an obligatory objective it's an special side quest. If you see that the quest might be to hard you can back away. But if what you referring is that you being alone and you want to complete it... Well I don't know what other thing to say than its not really impossible more like harder and we'll they can't do much public events are made for the community to tackle.