I have had close to a lifetime of experience in diverse fields, and the type of company, product or service, is not germaine to this question.
Here is the dynamic.
If a company is known to always be hiring, that is the LAST company for whom you want to work.
So, who should you be tracking?
You should zero in on the companies that never seem to hire.
I'm not kidding.
The companies that never seem to hire have happy people who almost never leave, sue their employer, or have disputes that lead to hard feelings and poor productivity.
This means that you want to start to generate friendly contacts within those companies. That means finding people who will vouch for you, recommend you, and work to get you hired, when the "time" comes.
Until that opportunity arrives, you must be ready to eat your "ration," so to speak, unless you step in a pile of gold that day on the sidewalk.
Luck is defined as that place where preparation meets opportunity.