10,000 saints is with jesus?

My question is about the book of Revelation in it Jesus is suppose to come back whit 10,000 saints along side him. What I want to know is that if all the armies of Heaven is with him and it's only 10,000 saints then are only 10,000 people going to be saved in the rapture. Also in Revelation when the church is first mentioned about being in heaven john said he saw a great multitude that was uncountable. How did the saints go from uncountable to only 10,000 which can can be counted. Can anyone answer this and if not then I come to the conclusion that not many will be saved in the end.