`sqlite3` ignores `sqlite3_busy_timeout`?

I use sqlite3 in multiple threads application (it is compiled with SQLITE_THREADSAFE=2). In watch window I see that sqlite->busyTimeout == 600000, i. e. that it is supposed to have 10 minutes timeout. However, sqlite3_step returns SQLITE_BUSY obvoiusly faster than after 10 minutes (it returns instantly actually, like if I never called sqlite3_busy_timeout). What is the reason that sqlite3 ignores timeout and return error instantly?