It's not a big deal until you come to upgrading to command!
Unless you have schooled yourself sensibly, you suddenly find you have the additional workload of navigating safely around complex airports (some of them which have yellow centerlines which are barely visible, looking for an inadequately illuminated stand being dazzled by the lights on the terminal building at night also looking for a marshaller who is not equipped with illuminated wands!) - whilst doing this you are monitoring the RT for any changes and also keeping a lookout for the odd errant vehicle or even a/c!
Ok, lots depends on good SOPs and having an FO that doesn't bury himself in the chart or the checklist, not to mention the odd one I have had that starts loading the FMC for the return sector before you've arrived at the gate.
And who is responsible if you biff anything?
Also if you haven't taxied the a/c ever before (ok you night have done the odd bit in the sim), you also have to learn how to taxi safely and smoothly.
Good game!