Like @jeffmarc points out, even if it doesn't get you to where you can have intercourse, using that pump is pretty important to the survival of your penis! Your penis can atrophy like any muscle and when the urethra is not being stretched it can shrink.

You might be thinking "it doesn't work so who cares" but you still have the option of implants and injections to bring your soldier back to full attention and if you didn't give it some TLC until you went down those paths then you might find that it's painful to have an erection or you've lost a lot of length and girth as a result of ignoring your buddy.

If your pump isn't useful for intercourse then don't look at it that way, look at it as "this is the device that keeps my member stretched to it's potential, even soft, so I have hopes of using it later". No different than lifting a 5lb weight every day to keep you from losing all your strength - you won't be in any body building competitions but you can at least show up to one.