Savings Leakage The gap between the savings you negotiated and what actually shows up on the P&L. Like squeezing a balloon — air escapes between the signature and the invoice.
Cost Avoidance Preventing a price increase (e.g., talking a supplier down from +8% to +2%). Real value, but not a cost reduction — spend still went up.
Hard Savings Money you no longer spend — confirmed by comparing actual invoices to the baseline. This is the only number finance fully accepts.
Baseline The reference price used to claim a saving. Can be the old contract price, list price, or a market benchmark — pick the wrong one and finance rejects the entire report.
P&L Impact The actual change in your profit-and-loss statement. Finance doesn't count savings until the invoice clears and the P&L reflects lower costs.