[SilasX]

>The reason children seem to learn quicker is because they're exposed to the language every hour of the day. They have no choice.

They also have an environment of understanding adults willing to explain their mistakes and teach how to say what they want.

If you’re already an adult, this is hard to find. People will either switch to your language, ignore you, or find some common language (even ad hoc hand signs) to communicate.

[gringoDan]

This is sometimes the case. But in my experience, a lot of people (strangers even) are more than willing to help you out. They are excited that you are learning their native language and want to see you succeed.

A good portion of the time, what you're describing stems from the language learner defaulting to an easier version of communication or trying to avoid embarrassment.