I need to squeeze a petal. Some glass gets so molten, it makes the most fragile-looking petals. I need to be careful - customers want to wear these, not put them behind glass (although some have done ;o)). Others stay so thick, they look more like buttons than leaves. They'll need teasing later, to give them flow and definition. Some don't like the mashers, and crack.
I need to bend the petals round the rose. Some melt so easily, the whole petal disappears before I can get the marver to it. Others stay rock soling like an ironing board, refusing to budge.
When all the petals are up, I need to tease the whole rose into shape, crimping, pulling, twisting each petal. Some glass doesn't like being teased. I understand that. I don't like beaing teased either.
Finally, if it's silver glass, there's a whole load more. Making a rose is perfect for striking glass. By default, the rose goes in and out of the flame, all the time. But glass that overstrikes is useless - it is impossible for roses, and only the last two petals turn out pretty. If it reduces, then what am I reducing? A rose has recesses - ever part of it is a different distance from the flame, protected by petals or exposed.
A rose is not a rose is not a rose - and that's why I love making roses.