There are instances where killing a new infestation of insects can be far better than trying to live with them, or use natural deterents.
I once moved into a house where soon after was swarming with fleas. They must have used some kind of insecticide that killed live ones but not eggs. We used flea bombs
I brought home a shirt from a garage sale and without thinking laid it on my bed. I got bedbugs and called an exterminator.
These kinds of insects don't just leave on their own and I feel the quicker they are gone the less harm is done to all
Once i was living in a rented room in a big block house. The whole house was swarming with fleas (they are bed bugs, but we call them "human fleas"). My landlady called an exterminator several times, but it wouldn't help. That was dreadful. It was dreadful that nothing could be done. Those beasties were devouring my ankles while i was sleeping. I got into hospital soon after i moved into that room (not because of fleas, of course), and mom and Liza paid that woman for the rest of the monthly rent and took all my garbage back to our flat in Kolpino. Fleas are a nightmare. God save us all from fleas.
What about other malicious insects,- once, "homey ants" appeared in our building's ventilation system. Mom called them "homies", because everyone thought they were cute! Nevertheless, with time, their quantity got reduplicated, and it became clear that they actually WERE causing inconvenience. Natural ways couldn't keep them from coming to our flat and eating our food. I was an omni then, and i remember them eating grease. They loved grease. Sorry for the details, but their favourite food was human undies. So, they were pretty gross in fact. They were crawling under lids of skillets where cooked meaty food was kept after cooking is finished (they also loved fried eggs), and they were dying on the surface of those products, so the products were covered with LAYERS of dead ants.
Anyway, everything changed when cockroaches came from the ventilation. Our flat had been always quite clean, so cockroaches didn't have very much to eat there,- yet they were still coming, and even trying to organize their nests somewhere around the flat and behind our gas stove! So dad sent us all (mom, Liza and me) to the country to protect us from the poison. He stayed at home, bought a lot of "Mashen'ka" (a super poisonous Soviet insecticide, mostly against cockroaches) and spilled "Mashen'ka" all over the flat. All cockroaches died, and those who were in the ventilation, either died or went away. The ants died too. Luckily, neither cockroaches nor ants ever came back.
That's interesting that those people who live by the (Black) sea, suffer from tropical cockroaches. They are nasty beasties. They never live at home,- they live outside. But they love dumpsters, a.k.a. food leftovers left in street dumpsters. Their body size is remarkable, and one can faint if he sees such a monster crawling across his feet (which sometimes occurs, though they never bite humans). Lol, that's why cats are taught to catch and kill tropical cockroaches from birth (btw, cats succeed).