If the 0-day can be sold, then what do the purchasers do to recoup their investment? Aren't attacks like this one of the main reasons that a 0-day will have val

If the 0-day can be sold, then what do the purchasers do to recoup their investment? Aren't attacks like this one of the main reasons that a 0-day will have value? Even malicious state-level actors will likely use the purchased vuln in an attempt to gain access to a target system (potentially via similar spear-phishing methods); although in that case their motivation will be access to information rather than financial gain.