An erection problem means that you routinely can't get or keep an erection that allows satisfactory sex. You may not be able to have an erection at any time. Or you may not be able to have one that is firm enough or lasts long enough to complete intercourse. The problem is also called erectile dysfunction (ED).
It's not the same as having trouble getting an erection now and then. That's common.
Erection problems can be caused by problems with the blood vessels, nerves, or hormones. They can be caused by diabetes, heart disease, and injuries. Nerve problems also can cause them.
Medicines, alcohol, and tobacco also can cause problems. So can depression, stress, grief, and relationship problems.