Do I have it all wrong?

[greenpassion]

I am going to lay out as briefly as possible my situation, and I'm doing so because I wonder if I should just give up on having orchids....

I have several phals, all of which have finished blooming months ago. I have several oncidiums which also have finished blooming. They are all grouped on a humidity tray, and all are in the correct potting medium for that species, they are under led lights at the correct height from the bulbs, and I have yet to see any new spikes beginning. I bought some of the phals at a grocery store, and some were gifted to me by friends. Anyway, on 2 of them I see good new root growth, and on 2 others, new leaves are slowly (and I mean SLOWLY) coming out, but that's it. No trace of anything else.
I was just carefully rooting thru the bark mix on one of the phals that is growing a new leaf, and found a mushy root. I have found several 'bad' roots on a few of these guys, even when at the same time they are still putting out those silvery white roots with the bright green tips.
What am I doing to get bad roots? I have been clipping them off at the junction of where the root looks healthy, and where it's gone bad. Is this right?
I have so many plants, tropicals, bananas, elephant ears, etc, and am sucessful with them. I worry I am a failure at orchids...