Over the years he drifted and accomplished nothing.
Tips
usage
跎 almost never appears alone, it locks together with 蹉 in 蹉跎, 'to fritter time away / let opportunities slip'. The whole word carries a tone of regret over wasted years.
The foot radical 足 (left-side form) supplies the imagery, stumbling, missing one's footing, which underlies the 'waste time, go nowhere' meaning of 蹉跎.