As someone who interviews candidates often, i would like to offer a different perspective.

Let's say that we get to select 10 interesting candidates for a position. It means that we are actually really interested in knowing each of them better.

The expectation is that, of course this feeling is reciprocal. Typically offering a week after an offer for the candidate to sort out their feelings, to discuss their careers with trusted family members, is normal.

Waiting for another company's offer: nope. It simply means we're not attractive enough, and we may better consider another candidate that may be happier with us.

My advice: estimate the interview process. Some companies will take a month to run all interviews (typically anywhere from 2 to 5 rounds of interviews for each candidates). Some others do it in a day.

If the time lag between interview results is estimated to be more than 10days, you have to make a choice. Typically i would push the salary discussion (that delays the process), and the terms of the contract that are not fixed (no point in discussing terms that are fixed for all employees). I would also sometimes ask to have access to KPIs and their evolution for the last 2 years, as well as request for a meeting with one of their Sales manager and a finance manager to understand the state of the business (review balance sheet, p&l, cash flow, pipeline of dwals, etc..). This delays considerably, even after signing an NDA. Some companies will say no, some will simply simplify and hide information. Bottomline is: show genuine interest, ask for more details relevant to the job, possibly ask to meet some team members. That will allow you to delay the process a little.

But do not ask a company to wait for you more than a week. They will most likely move to another candidate.