Lifeboat matches or a windproof lighter and some dry flammable tinder are fairly reliable in bad conditions.

A flame from a match or lighter is more effective than a spark, especialy in cold wet conditions.

Means of producing a spark such as a ferro rod and striker have the merit that hundreds, maybe thousands of fires may be started without re-supply. That could be a lifesaver in a long term emergency, but is of less importance if caught outdoors for a night or two of bad weather.