You need to have a plan in case of an emergency and typically you need some money to go with that plan: your Emergency Funds.
First, let’s define Emergency: something which happens unexpectedly, which you could not easily predict would occur at this moment. Examples include losing a job, having a severe accident or having to take care of a loved one. As you can tell, these mostly include losing or temporarily leaving your job, which means no income for some period of time.
Emergencies are not the fridge breaking down, car maintenance or a new roof. All of those you can easily predict will happen in the future and you need to plan and budget for those separately.
So, what to think about in terms of this emergency fund?
Mostly you need a plan for when the sh*t hits the fan. Make sure you are prepared.