本来 vs 原来 (originally vs it turns out)

Plan versus discovery

• You planned to take the bus, then found out your friend had been driving there all along.
• I / me我wǒoriginally本来běn láiwant to想xiǎngto sit坐zuòpublic transport vehicle公交车gōng jiāo chē，originally原来yuán láiyou你nǐto drive a car开车kāi chēcome来lái(completed / change)了le！ — "I was originally going to take the bus — oh, so you drove here!"

Both can mean "originally"

• originally本来běn lái / originally原来yuán lái + earlier state: he他tāoriginally本来běn láilived住zhùin在zàiBeijing北京Běi jīng = he他tāoriginally原来yuán láilived住zhùin在zàiBeijing北京Běi jīng — "He originally lived in Beijing."
• Before a noun with (modifier / structural particle)的de, both work: originally本来běn lái(modifier / structural particle)的deplan计划jì huà / originally原来yuán lái(modifier / structural particle)的deplan计划jì huà.

he他tāoriginally原来yuán láilived住zhùin在zàiBeijing北京Běi jīng。

Only originally原来yuán lái: so it turns out

• originally原来yuán lái announces a discovery: originally原来yuán láiis是shìyou你nǐ！ — "Oh, it's you!"
• originally本来běn lái cannot do this: originally本来běn láiis是shìyou你nǐ does not mean "so it's you".

so it turns out原来yuán láihe他tāis是shìa teacher老师lǎo shī。

Only originally本来běn lái: of course

Choose by job

• Discovery → originally原来yuán lái. Obvious from the start → originally本来běn láithen / just就jiù. Original plan or state → either.
• he他tāoriginally本来běn láiunexpectedly不想bù xiǎngcome来lái，afterwards后来hòu láifriend朋友péng yǒuto advise劝quàn(completed / change)了lehe他tā。 — "He didn't want to come at first, but then his friend persuaded him."

he他tāoriginally本来běn láinot不bùwant to想xiǎngcome来lái。

Recap

Read the full reference: HSK 4 grammar — Comparing similar adverbs.