Link Relevance

We are constantly being told by SEO experts and the Search Engines that the importance of a link is determined by its page rank and relevance to our own web sites. Consequently when developing a linking strategy we should only be concerned with relevant links. That is other web sites which have some connection to our own. For example I run a web site devoted to providing a variety of cleaning services to commercial clients throughout the UK, so a relevant site would be a cleaning machine supplier or a cleaning chemicals supplier. Not other cleaning companies for the obvious reason they are our direct competitors. Now this sounds simple and straightforward and if we did this we would end up linking to about twenty sites. This number is not in any way sufficient for us to compete with our competitors who have many hundreds and in some cases thousands of links recognised by the search engines. How does Google determine relevance? I would suggest that it is a completely random process. If I look at my own back links which Google are registering then many are relevant in terms of the definition above, but many are not. None of our suppliers who provide us with a back link and incidentally have high page ranks form part of this list and yet they are highly relevant? It may be that these form part of Google's count but they choose for one reason or another not to divulge these. It remains a mystery. How does a mathematical formula work out relevance? If I back link to my customers who are a very divers group to me they are relevant but apparently not to Google. We have many back links from construction and building companies because we carry out builders cleans for them. Yet these are seemingly not deemed to be relevant but a mortgage company is? Builders and construction firms are mentioned several times on the web site and so a relevant connection should be able to be made. If I look at the back links of my major competitors then the situation becomes even more confusing. Very few would appear on the surface to be of any relevance at all but who am I to judge? I do not have inside knowledge of the workings of these companies and their possible connections. To me the whole process seems completely arbitrary and I will continue developing links to sites that I consider relevant. If Google paid attention to its own advice in only developing links to relevant sites then presumably it would only link to other search engines? It is an easy statement to make for Google and SEO experts, 'only develop links to relevant sites' but the reality is that they have no way of knowing what is truly relevant and what is not. Consequently my advice is to continue developing your links to websites that you consider of some relevance either to you or surfers who come across your site and continue to be astonished at what Google considers to be relevant!