There are only a few million bitcoins in existence.
Therefore, the price will go much higher, or bitcoin will not be used around the world by millions of people.
If I wanted to send 20 million dollars in bitcoin, but the price of bitcoin was only $1.00, I would have to buy all the bitcoins in existence. And I still wouldn't have enough bitcoins.
Similarly, if 500 million people wanted to spend $10.00 a day in bitcoin, the price of 1 bitcoin would have to be a lot higher than $100. Otherwise there wouldn't be enough bitcoins for the system to work.
So a low price isn't necessarily good for bitcoin. It just means that there aren't many people using bitcoin.
The price of bitcoin is always at the right price. using your 2 examples - if you enter the market place with 20 million dollars to buy bitcoin you might well find you will not get them all for $1. they will go up. So you might only need say 5,000 bitcoins to send the 20 million dollars.
If 500 million people have bitcoin and want to spend $10 worth you might find they can do that by selling just a satoshi.
Unless you are buying and selling bitcoin to make money (speculating) then the price of a bitcoin is irrelevant. But whatever it is, it needs to be fairly stable as that influences peoples use (and extent of holding) it.
A lower price will though have a psychological effect on some and they may get involved with bitcoin becasue of it. eg if it goes to say $50 then people thknk "oh I cna buy one for $50". "That is quite good". If when bitcoin was $1,000 you said for $50 you could buy 0.05 part of a bitcoin they would see that as "not good' even though they are the same. The average person (and I am one) gets bamboozled when they have to visualise 5% for example. It is also why naming conventions for parts of a bitcoin are a topic in themselves