Force Click, as the name implies, requires you to put a little "force" behind your click.
By default, Force Click requires a "medium" level of intensity to activate. Apple gives you the option, however, of switching to "light", which makes it easier to engage, or "firm", which requires you to put even more muscle behind it. Whether you're having a hard time triggering Force Click, or you're triggering by mistake, there's likely a setting that's perfect for you.
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