Meaning of the word "where the rubber meets the road" in English

What does "where the rubber meets the road" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

where the rubber meets the road

US /wɛr ðə ˈrʌbər miːts ðə roʊd/
UK /wɛə ðə ˈrʌbər miːts ðə rəʊd/
"where the rubber meets the road" picture

Idiom

the point at which a theory or idea is put to a practical test; the crucial point of a situation

Example:
All the planning is done, now we're at where the rubber meets the road.
When it comes to actually implementing the changes, that's where the rubber meets the road.