JavaScript Nullish Defaults Visual

Inputs: [default value], [input fixtures], [expected preservation rules]. Explain the difference between nullish coalescing and logical OR when zero, false or an empty string are valid values. Include null and undefined fixtures. Show only explicit outputs; avoid claiming all falsy values should be retained without the supplied contract. Produce a two-lane value flow diagram that routes null and undefined to the fallback while retaining zero and false. Include one concrete verification step that checks the defining task detail against the supplied inputs. Use [audience] and [tone] to calibrate presentation.

Use the attached references only for the specified visual attributes. If a required reference is missing, request it before generation. Produce one finished image with a deliberate focal point, consistent geometry and clean margins. Keep any exact wording on a separate editable label layer or leave its area blank. Do not invent evidence or present an illustration as documentary proof.