Why is that?

Maybe it is just me but it seems like every time I find a product I really like a few years later it disappears into oblivion. The latest thing is my favorite brand of socks and though I can't recall the brand name,I would know it if I came across it. I spent 2 days in search of the socks,both online and in a local shoe store that once sold them and they have vanished without a trace. It wouldn't be so bad if there was some way to know ahead of time that they were going to quit making something,then at least you could buy some before they were gone or find out if they had changed the name but I don't see that happening as there really isn't a logical way to go about it. It seems to me that the things they quit making are cancelled because they work too good so they don't need replacing as much,or in the case of other products that you replace on a regular basis they want to sell you something inferior because they make more money from it. So is it about greed? Or have I slipped a cog and am getting even more paranoid?