Why isn't Earth tidally locked to the sun? Given that the moon has long been tidally locked with the Earth, why isn't Earth (or any of our other solar system's planets) tidally locked to the sun?
Really, it's just because the tidal locking timescale is so long for Earth:
$$t\propto\frac{a^6m_{s}}{m_{p}^2R_s^3}$$
where $a$ is semi-major axis, $m_s$ is the mass of the secondary object, $m_p$ is the mass of the primary, and $R_s$ is the radius of the secondary. If we compare the Sun-Earth system to the Earth-Moon system, we see
$$\frac{a_1}{a_2}\approx380,\quad \frac{m_{s_1}}{m_{s_2}}\approx80,\quad \frac{m_{p_1}}{m_{p_2}}\approx333000,\quad \frac{R_{s_1}}{R_{s_2}}\approx3.67$$
where $_1$ denotes the Sun-Earth system and $_2$ denotes the Earth-Moon system. To make up for these differences (and to have Earth be tidally locked by now), assuming similar Love numbers and dissipation functions for Earth and the Moon, we would need Earth's initial spin to be substantially smaller than the Moon's initial spin by many, many orders of magnitude, and this just wasn't the case.