Your GA4 lead history may not go back as far as you think. Standard properties keep user-level and key-event data 2 or 14 months.
In a standard Google Analytics 4 property, user-level data, including key events such as lead form submissions, is kept for either 2 months or 14 months, depending on your setting (Google Analytics Help). Standard aggregated reports aren't affected. Retention limits only apply to explorations and funnel reports.
You might think you can open GA4 next year and dig into this year's leads. The retention setting decides how far back your deeper analysis goes. Google's help page says:
If your lead-quality reviews use explorations, such as comparing which sources turned into sales, a 2-month setting can wipe out the history you need.
This article is general information. Google can change GA4 settings and limits, so check its current help page.
GA4 keeps user-level and key-event data for 2 or 14 months in standard properties, and only explorations and funnel reports are affected. Set it to 14 months if you can, and keep your real lead history in a CRM.
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