>>212520530
Sauron wanted the ring immediately so that it couldn't be used against him. That was Sauron's greatest fear, Gandalf/Aragorn/Galadriel would use the ring to destroy him.
The ring being lost by Golem was intended, being found by Bilbo was not. Sauron probably wanted it to stay hidden in the mountains while he built up his power and eventually crushed all opposition.