Standard error
The standard error says how precisely a value such as B is estimated: how much it would vary from sample to sample. Smaller means more precise. B divided by the standard error gives t, and from that p (Sig.).
Example: Time management: B = 0.24, standard error 0.06, t = 4.35 (≈ 0.24 / 0.06), Sig. < .001.
Caution: With more people the standard error gets smaller - even if the relationship stays the same.