That's correct when you're a business but not when you're dealing with consumers. Some of the latter will have no qualms creating new email addresses to "renew" their trial periods, effectively giving you free riders and bunk operational stats.
Look at current Flickr, trying to force users into a one-size Pro membership. They're not listening to light users who won't pay $50 + taxes + currency conversion fees to get 'stats and partner offers'. Instead people are creating multuple accounts and storing 999 photos in each, for free. Flickr should be in that space with $10 Basic accounts
If you've never run a business in this sort of industry, you would be truly amazed at the lengths some people will go to just to save a few bucks.
At an early stage of one of my businesses, the founders were literally sleeping in shifts because a small group of people was creating new accounts 24/7 and trying to scrape our entire offering piece by piece to work around the caps on individual accounts. So apparently our offering was good enough for them to try to clone all of it and presumably set up a copycat site, yet by your argument it was also "underwhelming" because they didn't want to pay anything for it.
Twice I've been stung for that - they're silent for the month, but as soon as you cancel (after navigating their dark patterns) they start the email bombardment.
Requiring payment details for a "free trail" is a huge red flag for me now - simply because it tells me what type of company it may be.
- If you don't give full access to what you're offering during the trial period, would-be users won't get a feel of what they might be losing out on when the trial runs out.
- If you do give full access during the trial period, but don't require some kind of hard to get unique enough identifier, a non-negligible users will create new accounts ad nauseam.
(Alternative unique identifiers could be SSNs or ID cards or physical mail addresses. But these are all non-starters. And phone numbers and emails are free for all practical intents.)
Can you speak more to your comment that phone numbers are essentially free? I know with something like Google voice you can get one free number (which still needs to be associated with a non-GV number). How would you get many phone numbers for free?
Also, the original comment specifically mentioned free phone numbers, not cheap or otherwise not-free numbers.
The negligible part is the cost of the freeloaders, there can also be value in freeloaders. They help spread the word and keep up the good word and they might convert rather than going to a competitor. They also represent a good opportunity to show good will.
The non-negligible part is the lost revenue from performing such shady practices as requiring a cc / phone number. If you require that for a trial I will perform extensive research of your competitors. And if desperate enough might consider you after that if nothing else was up to par.
If you allow me to sign up for a trial without an email that is very positive and shows me that you respect your users. That is very appealing.
And very reasonable, because the sole reason for anyone to ask for an email is so they can send spam to it afterwards. Which of course shows me that you do not respect your users.