"If your CAD model only works in CAD, it’s not finished."

I see this all the time
Beautiful models. Clean renders. Perfect mates.
Then the part hits the workshop…
• Weld access isn’t possible
• Tolerances stack up
• Assemblies don’t install in the real world
• Someone says “we’ll just make it work”
That’s not a manufacturing problem.
That’s a design problem.
Good engineering isn’t about making something look right on screen.
It’s about designing for:
Tool access
Real-world tolerances
Assembly sequence
Human hands, not idealised constraints
If a fabricator, machinist, or assembler has to “figure it out”, the design isn’t finished yet.
CAD is where ideas start — not where engineering ends.
Curious to hear from others:
What’s the most common design-for-manufacture issue you see in the real world?