No-one should expect engagement - I like to try to return at least some types of engagement, but I don't expect others to automatically do the same. I don't know what their circumstances are, and I don't know how many other people they have in their network to engage with. It's just not possible to keep up with everyone!

I obviously and naturally end up engaging more with people who engage with me - it's human nature, whether online or offline. And I do keep a list of people who leave comments, for example, so that I can - eventually - return the favour. But I try not to set too many restrictions for myself in terms of having to engage - it's more important to be polite, and be as genuine as possible. :)