One of the interesting things I've noticed while learning languages is how people develop accents. I will not get into depth with it, but I will point out what I like to call the "Addis Kid English" (I'll probably change the name).
This refers to (but not limited) the people from major cities who are well versed in pop culture, western lifestyle, science and technology. They speak English nearly with a native fluency, but something sound off. You guess maybe it's the rapid transition between Amharic and English, or they're code switching, or they're over enunciating things ... you just can't put a finger on it.
If you pay attention, they(we), pronounce difficult words with ease. But then some words, simple words, just give it away.
Try saying these out loud: "said it", "Determine", "to develop", "Developer", "aluminium", "logarithmic", "Pythagorean", "conjugations", "abbreviation, "image"
Now say "Pathetic", "aesthetic", "Spiderverse", "colleague", "Megatron", "lowkey", "Pep rally"
Chances are you butchered the first set of words, and sounded a bit more native on the second set.
That is because your accent adopts words based on how it heard it first.
If you learnt words from your local teachers at school, their accent is subconsciously embedded in your head. But if you learned words for the first time from native speakers (movies and such), you'll sound like a native. That is why there's usually this rather unpleasant, borderline annoying cadence when people speak with the "Addis Kid English".
Next time you say a word, pay attention to it. Did you learn that word the way your biology teacher in the 7th grade said it, or did you learn it from a native media.