Phalaenopsis repotting
 

I just repotted a Phalaenopsis for a friend. It had an unusually long neck and I wondered if I should trim some off the bottom. I didn't as it looked like there were some healthy roots developing along much of its length. Should it have been trimmed?

I would never cut off viable roots, especially if the plant doesn't have a huge amount, like this one. Eventually there will be a stub at the bottom with no living roots coming from it; THAT can be cut off.

I agree, if the roots at the bottom were dead then I would have cute them off. It will need all the roots it has.