Actually, crimp connectors are used in automobiles and other appliances for speed of assembly, not reliability. The idea that a soldered connection is not as reliable as a crimped one is false. When there are vibration issues, enough slack is given to wiring looms to avoid the problem of fatigue. A crimped connection is just as succeptable to this kind of stress as a soldered one.

While crimped connections can be very secure, soldering is the only way to achieve 100% connection between two electrical components. Crimping is simply faster for assembly line use, while soldering is very labor intensive.