You put in two years. You can read a news article, you know the grammar, you've got a solid vocabulary. Then you're in a room with Lebanese people talking to each other and you catch perhaps a third of it. This is one of the most demoralising experiences in Arabic learning, and it is entirely predictable.
What happened
You learned Modern Standard Arabic. People are speaking Lebanese.
MSA is the written and formal standard across the Arab world — the language of news, books, formal speeches and education. It's nobody's first spoken language. Children acquire a spoken variety at home and meet MSA at school.
So a conversation between Lebanese friends isn't a colloquial version of what you studied. It's a related variety with its own sounds, its own everyday vocabulary and its own grammar patterns. Linguists call this situation diglossia, and Arabic is the standard textbook case of it.
Where the differences bite
Sounds. Several MSA consonants are realised differently in Lebanese, and vowel qualities shift. Your ear is tuned to forms that aren't being produced, so words you know go past unrecognised.
Everyday vocabulary. The highest-frequency words of daily life — want, now, like this, a bit, how, what — frequently differ. These are the words holding every sentence together, which is why losing them costs so much comprehension.
Grammar patterns. Verb forms, negation and question structures work differently enough to disrupt parsing even when you know the words.
Speed and reduction. Fast connected speech compresses and drops things, as it does in every language. You've mostly heard careful MSA audio recorded for learners.
Note for Sally: a short list here of the most disruptive everyday words that differ between MSA and Lebanese would be the most useful paragraph in the article. Three or four, in your transliteration.
Why this isn't wasted work
It genuinely isn't, and this is worth sitting with before you conclude the two years were pointless.
Your vocabulary largely transfers. Your grammatical understanding transfers. Your reading transfers entirely — that's the skill MSA is actually for. And having MSA makes a second Arabic variety considerably easier later.
What you're missing is a specific and learnable layer: the sound shifts, a few hundred high-frequency words, and a handful of structural patterns. That's weeks of focused work, not years.
What to do about it
Learn the correspondences explicitly. Which sounds shift, which function words differ. These are rules, not a vocabulary list, and once you have them a lot of speech becomes audible.
Listen to real Lebanese speech. Television, music, podcasts, people talking to each other. Not learner audio.
Speak with a Lebanese speaker. Your MSA-flavoured Lebanese will be corrected in real time, which is faster than any amount of study.
Expect your MSA to interfere for a while. You'll reach for the formal word. People will understand you and find it slightly funny — the equivalent of someone speaking in a register from a different century.
The reframe
You don't need to start again. You need to add a layer to something substantial you already have — and you're much closer than the experience in that room suggests.