pronouns - When is it correct to use "yourself" and "myself" (versus "you" and "me")?

I'm confused by why people use the following:

It's up to yourself.

Rather than:

It's up to you.

Another example of this would be:

Please feel free to contact ourselves if you have any problems.

Rather than:

Please feel free to contact us if you have any problems.

Are both of these correct? Is there any reason for using the former?

Answer

Using "yourself" and "ourselves" in these contexts is incorrect.

"Yourself," "ourselves," and "myself" are reflexive pronouns, correctly used when the subject/actor of the sentence and the object/recipient are the same person or group.

"I see myself" is correct because I am doing the seeing and am seeing myself. In your latter example, the subject is the implicit "you" and the object is (correctly) "us."

Edit

I searched for a clear reference for this. The clearest one I found was Wikipedia's reflexive pronoun article, whose Non-reflexive usage in English section indicates that the usage you refer to is "non-standard and incorrect."