It's not instant. Transfers can be delayed for hours in some cases.
It has ridiculously low limits that cannot be raised.
Until recently it had a cumbersome question and answer system with strange character limits for each.
Virtually no businesses use it. You can buy weed (illegally) using it because they can't use credit card processing.
A revamp to the Interac system is in the works which looks similar to the UK faster payments. A frankly much better system.
https://www.theglobeandmail.com/business/article-interac-cho...
Really, the existing autodeposit feature would be perfect if it let you log in to your online banking and confirm pending transactions before autodepositing them. For that matter it would be nice if the email gave me a string I could paste into my online banking to get to the existing confirmation page.
It's all much better than having to link your bank account to some third party or give away your credentials though.
Similarly, we won't be able to get rid of email but if clicking a link in an email opened an app instead of a webpage, it would be a lot harder for phishing websites to pretend to be my bank. (Assuming I'm expecting a mobile app, of course. A second line of defense is that my password manager might not prompt me to fill in the password because the URL doesn't match. But even that's not foolproof.) Even better would be if Interac E-Transfer itself was an app I could sign up for, then it could send me a push notification and I could skip my inbox entirely for these sort of transactions.
Of course, the only reason I trust apps more than websites is that I went to download them previously, rather than clicking a link that just showed up in my inbox. To that end, Gmail and other email providers have immense power if they created a design which could highlight emails from senders I've seen before as "trusted" and those from unknown senders as unknown.
Things get more gray-area though when the system itself fails: You can request money from anyone using Interac E-Transfers, and that means spammers could hijack a bank account and request money from friends and relatives you've recently sent e-transfers to, for example. Those emails would then appear as "trusted" and there's not much you can do to stop that, it's the cost of making money transfer "easy".
The problem comes when banks are able to argue that their half-hearted security means they aren't liable to pay for the consequences. Consumers need protecting against that.
† In the UK we have a lot of 3-D Secure, developed by Arcot. But of course the average consumer has no idea who "Arcot" are, and so no reason why they should distinguish an arcot.com site (legitimate, you're supposed to give them credentials if necessary to authenticate you) versus say badguy.example (a hypothetical phishing fraud). Both of them can show you branded imagery from your bank, both have a padlock, both claim they're keeping you safe. How should an ordinary person know?
Even now you never have to pin in the US.
CB dealt with Gemplus to add chip to all new cards emitted since 1992 so we had them for a long time. I don't know how it spread over europe, but as we had the industrial capacity to provide chip cards to everyone and a free market, I think it was easy to sell that to lots of european banks. CHIP+PIN is a really great deal for banks : it's cheap and the responsibility of all payments made with the PIN is on the card owner and are really hard (or impossible) to dispute.
I've been to stores in the US where they just swipe your magstrip and hand you back the card. No signature, no pin, they don't even look at it, so you can basically clone cards like it's still 1985.
This is consistent with how my UK bank treats any transaction occurring in the US: usually it's an instant card block and a polite phone call from them to check that it was actually me.
Sounds like the other response about transaction fees is on the right track.
The big kicker for me is Interac e-Transfers, where you simply log into your banking and can email (or text) money to anyone in the country - they click the link in the email/SMS they receive, log into their bank account, and choose where the money is deposited. We've had this system in place since at least 2014? Hell I pay my rent and buy weed just by sending e-transfers, they're treated the same as cash and happen instantly. I reminds me of something that happened recently, I stumbled into a conversation with some of my American friends trying to figure out how the one person was going to pay the other >1000 miles apart; it was absolute lunacy listening to them decide between PayPal, Cash App, Venmo, etc., trying to figure out who had the lowest fees for both parties, factoring in the time it takes for the transaction to happen and transferring to/from their bank account if necessary. It's insane to me how the banking system underlying the world's largest economy is so far behind the times.