Bertil
You can check chapter 10 and 11 of Keynes' General Theory… if you want a very detailed personal account of those.(Keynes was the best speculator of his time, and make Cambridge King's College immensely rich doing so.)
A simple example: my brother sells pearls. He considers other pearl sellers as competitors, but actually the more people see pearls being worn, then more they'll assume it is a legitimate jewel — so diamond sellers are his real competitors, and other non-stone gems should help legitimize his business. Therefore, when he can't accomodate a prospect (say, he doesn't have the right color) he should advertize for other pearl providers.
Another similar tech example: e-mail; the more companies used e-mails, the more IMAP became a useful protocol. The complete opposite would be ERPs: it's much easier to share the same ERP as your customer & provider. Therefore, if you are a competitor of SAP (the ERP for BigCorp) trying to specialize towards SMB, you spend a lot of commercial effort to explain the benefits of ERP in general to small businesses, only to pave the way for them switch to SAP——because that's what their customer use, and those are too big to change.
That why you have many e-mail providers, several cell phone makers, but only one dominant search-engine, one dominant ERP provider, one dominant social network, etc. To tell the difference is hard —— for instance, encouraging open standards might help your customer to switch to the leader more than it would help you offer a compatible service.
I'd love to help you (all that is what my PhD is about ;) but I'd need more detail about your specific industry.