Most homemade DIY PCB Prototypes may not withstand peak currents; at least not for a long time. This is because all through their making process, the greatest factor of consideration is basic functionality for a proof of concept.
A professional PCB design should not only be able to cope with peak currents but also other currents anticipated in the circuit. These includes Overcurrent, Short-circuit and Peak currents. When the circuit experiences some Overcurrent, the circuit traces should be able to let the Overcurrent Protection circuit to shut down without the traces blowing up. A professional PCB Circuit should also be able to handle a short circuit. This makes it possible to repair or recover the PCB from the damage since only such components as fuse will get damaged.
Peak currents can be experienced especially when you just power up the circuit. An example of such a circuit is the motor driver circuit. The instance when you power the circuit, the current rises up to some peak value. After a short time, t, the current drops to some steady value. This steady value can be referred to as the operating current. The circuit design should be such that it can withstand this inrush current. Generally, the thickest and the widest traces which are far apart from each other are always preferred. However, there is always a size limitation and the achievable quality of the PCB. The smaller the PCB, the harder it becomes to keep it safe from peak currents.
When designing a professional PCB prototype, it is advisable to always use the PCB trace calculator and also the via calculator. This is helpful in making the right decision about the geometry and the width of a trace and also a via. As a result, when the PCB is subjected to peak currents, it is able to survive the temperature rise better than the components held together by the PCB assembly. For home made DYI PCBs, a quick solution would be to solder some thick copper wire along with the high current PCB trace. This will be helpful in making it withstand the high currents within the circuit.