So. Let's say you have a job, or you're about to start a new job. Let's say your old job was Mother of Three and your new job is Mother of Four. It's a COMPLETELY different job and it changes every day, because the ages of your children will really affect the job. Also, the times of year will affect the job. Like, during the school year, your job will be easier because part of your job will be done by someone else for a few hours a day. But during the summer and holidays your job will be harder because there will only be you to do your job AND your children will be MAD because they sort of like the other person that was doing some of your job better than they like you. Also, sometimes you won't get to sleep in your job because the amount of daylight you see in a day will change and it will affect your children's sleep habits. Sometimes, they will stay up super late and still wake up super early and get extremely grumpy and difficult from, oh, about noon on until bedtime. So not only are you super tired, but everyone is grumpy and badly behaved.
Also they are LOUD. Like maybe you used to work in a factory where OSHA would have been called in to protect your ears but this is louder, your four year old is louder. And maybe your middle kids are struggling with some jealousy issues so when you take the baby for TEN LOUSY MINUTES to put her down for a nap, maybe the middle kids subconsciously but still purposely make a shitload of noise and wake up the baby seconds after she falls asleep. Then the baby is grumpy because she can never nap. Then she too sleeps badly at night because she is all janked up from not sleeping all day.
So. You are losing your mind, say, and it's only JUNE. And you have no one to talk to. Because if you say it to anyone, you are not just bad at your job, but you are a bad mother. You don't think you're a bad mother, but you are starting to think you are a bad and unlucky person.
In short - WORST. JOB. EVER.