The complete description of the lifetime of a droplet on a solid substrate evaporating in a 'stick-slide' mode is obtained. The unexpectedly subtle relationship between the lifetime of such a droplet and the lifetimes of initially identical droplets evaporating in the extreme modes (namely the constant contact radius and constant contact angle modes) is described and summarised in an appropriate master diagram. In particular, it is shown that the lifetime of a droplet is not, in general, constrained by the lifetimes of the extreme modes.

A physically credible relationship based on the unbalanced Young force between the initial and receding contact angles of an evaporating droplet is proposed and used to give a complete description of the lifetime of a droplet evaporating in an idealised stick-slide mode. In particular, it is shown that the dependence of the lifetime on the initial contact angle is qualitatively different from that when the relationship between the initial and receding contact angles is not taken into account

The manner in which the extreme modes of droplet evaporation (namely, the constant contact radius and the constant contact angle modes) become indistinguishable on strongly hydrophobic substrates is described. Simple asymptotic expressions are obtained which provide good approximations to the evolutions of the contact radius, the contact angle, and the volume of droplets evaporating in the extreme modes for a wide range of hydrophobic substrates. As a consequence, on strongly hydrophobic substrates it is appropriate to use the so-called "2/3 power law" to extrapolate the lifetimes of droplets evaporating in the constant contact radius mode as well as in the constant contact angle mode.

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