Y'all are so experienced, growing the orchids you do. I just clumsily grow mine the best I can. I know that I am often simply lucky that my plants live at all.
The one thing I have certainly learned the last four years, growing so many plants from flask, from compot, and from plug, is that the younger the plant, the more difficult it is to grow. I will lose some from my tiny seedling purchases, but for those that survive a year and particular the second year, they really seem to take off. This is the second year for lots of my varieties, and I am seeing growth and roots like never before. I just call this "Getting them over the hump".
@Ursula, when you say "full sun", are you referring to the sun that penetrates your glass roof or is that/those plants outside, truly in full sun?