What's the reason for using quotations with titles of works?

I have seen that in some styles for documenting sources quotations marks are used for the titles of short works.

What's the reason for setting this as the convention? This seems like a use-mention conflation.

e.g. One of Robert Frost’s most famous poems is “Mending Wall.”

Why isn't capitalization of the title a sufficient indicator that it is a proper name? Why require the additional quotations?


Welcome!

The use of quotations is to substitute for the absence of the italic font. In published texts titles will be (should be) written in italics to set them apart. Few typewriters (remember those) had the luxury of assorted fonts. The answer was to surround a title with quotes. The practice continues even though today's choices of fonts extend beyond the horizon.