Negotiators demand more whenever their adversary weakens. [causal]
As the peace wranglings drag on from one stage to another, one needs to bear sympathetically in mind the various deep-seated neuroses and inhibitions besetting the Algerian negotiators; an underprivileged people who for over six years had fought the grimmest of wars against a nation gifted to the full with every advantage of civilisation; a people aware that several times in the past their birthright had been stolen by guile, whether by fraudulent elections or unfulfilled promises (and how easily, on the very edge of success, might they be cheated yet again by French wiles or a foot placed incautiously!). On the other hand — as time passes on, moving ever to the disadvantage of the French — one must not ignore that all too human instinct of mankind to ask for more as soon as it realises that its adversary is floundering.
Horne, Alistair, A Savage War of Peace- Alge…, loc. 1418