You never achieve success unless you like what you are doing.

The line links “success” not to status or money but to sustained engagement: genuine achievement is unlikely if the work itself feels alien or joyless. Carnegie’s broader self-help message often emphasizes enthusiasm, interpersonal energy, and the long-term power of attitude; here, liking one’s work functions as the fuel that makes persistence, learning, and resilience possible. The statement also implies a practical test for vocation: if you cannot find satisfaction in the daily process, you may not endure the setbacks required for mastery. It’s less a romantic claim that work must always be pleasurable than an argument that durable motivation is a prerequisite for meaningful accomplishment.