I understand that the idea surrounding quelconque(s) when it is placed after a noun is similar to n'importe quel i.e. the noun "doesn't matter".
Choisissez n’importe quels stylo que vous aimez. = Choose any pen you like.
According to CliffsNotes the difference between the two is that quelconque has a "further emphasis on 'any sort' or 'any kind'". For example,
Choisissez quelconque stylo que vous aimez. = Choose any pen you like.
But because of the word quelconque you can choose literally any type of pen e.g. a ball point pen, a brush pen, a technical pen, a quill.
My question is the following: according to CliffsNotes, "when quelconque precedes the noun, it has a negative connotation."
However, they don't provide an example of this and so I don't know what they mean by this. So, could someone please create several examples.
Also, if my understanding on the difference between quelconque and n'importe quel is wrong, please can someone correct me.
<a class="blue-link" href="https://www.cliffsnotes.com/study-guides/french/french-ii/french-ii-indefinites-passive-voice/indefinite-adjectives" target="_blank" style="outline: none; color: rgb(28, 175, 246);">https://www.cliffsnotes.com/study-guides/french/french-ii/french-ii-indefinites-passive-voice/indefinite-adjectives</a>