Choose variable names that prevent conflicts with system variables, external tools, and variables in overlapping scopes. Use prefixes or distinct naming to differentiate purpose and avoid unintended overrides. For system/tool conflicts, use prefixed names: ```makefile # Instead of LDFLAGS (conflicts with rpm/deb packaging) GO_LDFLAGS ?= -s -w -X ${PKG}/internal.Version=${VERSION} ``` For same-scope conflicts, use different names for different purposes: ```dockerfile # Instead of same name for ARG and ENV ARG GIT_COMMIT=unknown ENV DOCKER_COMPOSE_GITSHA=$GIT_COMMIT ``` This prevents situations where variables are unexpectedly overridden by external tools or conflicting declarations in the same context.