Be an expert or be a Swiss army knife
You have to decide whether you want to focus on one skill or be ready to take over many things at once.
Back at my previous job we had a guy whose mainly job was to support IBM VIO servers. The problem? There were just 8 on a 600 environment. He was good, in fact, he was great. He could tell the solution for most errors just by reading the error code… but he would not be able to help on anything else (or rather tried to avoid any other work).
On the other hand, you have the people who don’t care about one technology but many. I am one of those, I just don’t like being tied up to one product or technology but many. The good thing about knowing a little of many things is not only that it may make you look smart (ha!), but having bits of knowledge from different topics allows you to integrate them and achieve higher goals, while lowering the barrier to learn new things as well.
Imagine you are a child, it’s your first day at school. Your parents have decided that instead of leaving you on a regular school where you would learn several topics, you just go to one which is solely focused on math. By the time you graduate, you are an expert on that topic, but it will be hard as hell to get you doing anything else apart from numbers. The whole situation is rather impossible, as it would require you to learn to read in order to understand math books, for example.
Now imagine the same at your job. You have been hired to be the expert on product Z, but you don’t know anything about products Y, X, W which are related to Z in many ways. By the time you are introduced to the other products, you have two options… one is to learn to use them, the other is just to hope someone else will serve as a bridge for your lack of knowledge on those products. Do you think this is impossible? Think again. On every company you have people that will likely say “Hey, I only know Z, no idea what’s that error from Y”, and they won’t even try…
The sad part of this lack of vision is that while it affects whoever is taking that bold decision of not supporting ‘anything else’, it also affects the business, and more important, everyone around him/her. You end up being a lost island on the ocean, as nobody can “bridge” with you and/or your knowledge.
If by any chance you are in this situation right now, it’s not late to fix it. Just try to understand how other technologies fit in the bigger picture from what your company or team is doing, and try to help other people to see the potential on your product as well. If that does not motivate you enough, then think on the worst scenario… what if I’m fired tomorrow? That may do the trick.