Acting is a difficult role to fill. You can’t make any excuses whatsoever because no matter what happens to you, the truth is nobody really cares whatever reason you had that you couldn’t learn your lines. Taking your pets to the vet and doing your part to take care of them won’t matter because there are always dozens of people that would be more than happy to take your place. Life won’t go your way all the time and the times it does are the times you can count it as a blessing. Whenever something goes wrong which isn’t even your fault, you may start to feel helpless.
Since these external factors are out your control, you might start doing something that is known well in psychology as learned helplessness. You begin to contribute everything to powers beyond your capabilities to manage and in many cases, this can lead to depression. But it still won’t matter to the people taking your audition because they still have at least five other people who didn’t have that kind of luck and will just choose one of them instead. Acting isn’t an easy career you’ll find many out-of-work actors working part time jobs as waiters or other occupations they feel they can do on the side.
It isn’t fair, many actors like Christian Capozzoli have to put every bit of energy they have in their body to make the best out of their situations. There are no excuses in the acting world after all. If you think you might get late because of traffic, show up and hour early and practice your lines. Read the script. Every day should have at least one concrete effort towards the building of your acting career.