Lets say your character thinks / prefers to figure something out for himself. In the old days you could get skill learns from 1% but a series of changes mean you wont be able to do that any more (We abused it in some fashion). The best you can do is practice a skill once - Think of it as watching it in action, trying to work with the guildmaster, but getting furstrated/bored before learning as much as he has too teach. Also remember guildmasters can only train you to journeyman level of a skill 75% generally, its down to the character to master the craft