False.
Large structural failures can be catastrophic and unexpected.
Buildings can and do collapse quite suddenly. The examples here are not necessarily caused by reinforced concrete failures (though several cases make use of reinforced concrete --- generally other failures lead to the collapse). But the final failure of a system under load and near its structural limits can be quite sudden.
Taiwan bridge: https://youtube.com/watch?v=OSCPUGHUyIs https://youtube.com/watch?v=WqHXMswLwPM
Minnesota I35W bridge collapse: https://youtube.com/watch?v=CMdv2wRaqo4
Jerusalem dance floor: https://youtube.com/watch?v=5UOb7RBWlak
Morandi bridge, Italy: https://youtube.com/watch?v=V479srTBlAk
Hard Rock Hotel New Orleans (under construction): https://youtube.com/watch?v=WC8k5unvyfU
Sampoong Department Store, Korea (visualisation): https://youtube.com/watch?v=aQXTSR9koCg
The Kansas City Hyatt Regency skywalk collapse (1981) would be another instance. I don't believe there's video of the failure itself, though Grady from Practical Engineering has a great explainer of what went wrong: https://youtube.com/watch?v=VnvGwFegbC8