Quotes - accounts vs. LEADS

Hi all,

I might just be me;

but I am little suprised I can not make a quote under “LEADs” - or go to quotes, and then allocate a quote to a LEAD

In my world, a LEAD is a LEAD until the day the buy something (why else have the leads option)

So basically the question I am looking to answer: How can I create a quote to a lead?

Goto Admin>Studio and make a relationship between Leads and Quotes

Thanks,
I have, however, no idea how to do so??

but how come, it is not set by default ?

Anyone with a hint on how I can make this "
Goto Admin>Studio and make a relationship between Leads and Quotes"

Any advise - at all?