Of course misfortune and timing matters but even then the points that I made affect both of these things, being a large dense international city will increase the chances that the virus enters the city's walls and when it's inside density, populaiton and public transport traffic will allow the virus to spread quickier and in larger pool. If you compare Milan and Rome subway ridership, Milan has a higher traffic, from a business standpoint Milan is also Italy's heart and is more connected to the rest of Europe, it has three times Rome's density and they roughly have the same population.
If you compare Western European countries to Eastern European countries, you have to look at which places have actually been hit hard, it's easy to see why they have been hit before lockdowns and why it spreaded that quickly in their areas. It's not entire countries that have been affected or are doing badly.
Now your general point about misfortune and timing is relevant if we use Mulhouse as an example, it's a particular international event that caused their cluster, that's misfortune and bad timing but for the majority of cases, they were simply in the most vulnerable areas, which doesn't mean that similar cities in other countries will necessarily be affected, Moscow being an example.
