In Othello, love is a force that overcomes large obstacles and is tripped up by small ones. It is eternal, yet derail-able. It provides Othello with intensity but not direction and gives Desdemona access to his heart but not his mind. Types of love and what that means are different between different characters.
Othello finds that love in marriage needs time to build trust, and his enemy works too quickly for him to take that time. The immediate attraction between the couple works on passion, and Desdemona builds on that passion a steadfast devotion whose speed and strength Othello cannot equal.