My friends consider me somewhat of a Grammar and Pronunciation Nazi. It grates on my nerves to see and hear words/phrases spelled and pronounced incorrectly. A mispronunciation that I have heard frequently is the word “important.” I could understand a non-native English speaker getting this wrong, but this should be an easy one for native English speakers, people.
I have heard this mainly from the 30-and-under crowd, so it seems to be a generational thing. The correct pronunciation is \im-ˈpȯr-tᵊnt\. Many in this age group have been heard saying \im-ˈpȯr-ᵊnt\. And in winter, one might wear \ˈmi-tᵊns\ but not \ˈmi-ᵊns\ as is frequently heard.
Curious, I looked this up and there is actually a name for this phenomenon. It is called T-glottalization and occurs frequently at the end of words in standard American English, like when we say “pop.” Notice that the first “p” is pronounced with some force behind it, while the same letter at the end of the word is all but non-existent – unless followed by a vowel sound, as in “pop a balloon.” HOWEVER, when this sound occurs in smack-dab in the middle of a word, well…it just shouldn’t be done!
 Merriam-Webster. (n.d.). Important. In Merriam-Webster.com dictionary. Retrieved August 2, 2021, from https://www.merriam-webster.com/dictionary/important
 Merriam-Webster. (n.d.). Mitten. In Merriam-Webster.com dictionary. Retrieved August 2, 2021, from https://www.merriam-webster.com/dictionary/mitten