If your ZZ plant looks like it needs to be reset, repotting in the same pot will be best. TheZZ plant's stems can grow quite large and begin breaking off the bulb if the stem is becoming too heavy. A stem breaking off from the ZZ plant's bulb, may prevent that particular bulb from reproducing. If you see a ZZ plant stem look like it is damaged or effecting the growth of the rest of your ZZ plant plant, repotting your plant will establish a more secure environment for your ZZ plant to continue to grow.