Never connected it with the word "deflation", but I guess I figured out a counterargument as a kid: back then, if you bought a mobile phone contract, you'd find yourself regretting it in less than a month, because the same company now offered a better deal; few months later, a better deal with a better phone. And here you are, locked into a static deal for the next two years.

But well, you have to buy that phone eventually, right? So you take the best deal you can find, and stop worrying about it. That's the only sane way.

So in general - customers will delay purchases until the reasons they want to make the purchase outweigh the expected savings from delaying further.

I've also found the reverse to apply: for example, taking out a mortgage, I opted not to hurry despite fast-rising prices, because I judged the money saved on doing it earlier would not offset the mental cost of adding a house searching and mortgage process on top of two other highly-taxing life events.

Until they don't:

The Osborne effect is a social phenomenon of customers canceling or deferring orders for the current, soon-to-be-obsolete product as an unexpected drawback of a company's announcing a future product prematurely. The term was coined in reference to the Osborne Computer Corporation, a company that took more than a year to make its next product available, and eventually went bankrupt in 1983.

https://en.wikipedia.org/wiki/Osborne_effect

That just adds jitter on a month to month basis. Purchases remain nice and steady over time.

That doesn't appear to be a real effect for the electronics industry in general. When Apple announces the iPhone 13 consumers keep buying the iPhone 12. Retailers just cut the price of the older model to close out their stock.