As per [BIP-340, footnote 14][fn]:
> Verifying the signature before leaving the signer prevents random or
> attacker provoked computation errors. This prevents publishing invalid
> signatures which may leak information about the secret key. It is
> recommended, but can be omitted if the computation cost is prohibitive.
[fn]: https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki#cite_note-14
