By implementing web-font, your website visitors can perceive the text in desired typeface even when one is not installed on their device (as system-fonts are).1
In contrast to system-fonts, web-fonts can often emphasise uniqueness and originality. They are one of the instruments used to make your brand more outstanding.
The more custom and rarely-used the typeface is, the more the above phenomena are felt by the website visitors, mostly subconsciously. But...
Besides the advantages they offer, web-fonts are not appropriate at any cost. They should be implemented with caution in order to avoid some commonly overlooked troubles. The following aspects should be considered:
A rarely used type has a good chance being unusual to the readers, as readers are not quite used to unusual forms. The headlines might be appropriate and even interesting looking in such typeface, but the main text requires good legibility and clarity.
Make sure readability is good enough, otherwise the written content will be harder to absorb by your website visitors. The appropriate balance between uniqueness and usability can be beneficial.
In general, our website visitors’ displays still have pretty low pixel density, mostly on computers.2 Because of low-rendering accuracy, the (web) fonts could look less clear there, especially the ones from the Serif family or in small size.
What to do? Verify how the desired web-font is rendered on such displays. Note also that some system-fonts are customly pre-adjusted so they can render the content more effectively.
Make sure how your (web) typography responds at various text-rendering.