I have a phalaenopsis and recently had it lose 2 of it's buds. I am new to orchids and am not sure what the problem could be. There were 4 buds, but 2 looked as if they were close to opening (you could see the purplish color through the bud) then they turned yellow and fell off.
My thoughts are maybe it is too cold? The house is kept at about 65 degrees.