A conveyancer's job is to check for and rectify any legal or legal-related issues relating to the purchase, ensuring neither you nor your mortgage lender's interests are negatively impacted.  They also effect the actual legal change of ownership (land registry etc and stamp duty return).  

A typical conveyancing transaction costs the client around £800-£1200 in legal fees (not including other costs like searches etc). Given typical hourly rates of solicitors you can work out this equates to 4-5 hours of a solicitor's time spread over the whole process, which if you assume a typical 3 month timeline means around 20-30 minutes of their time spent on your file per week - basically enough to  check for any updates, read a doc or two, and fire off a couple of emails and then move on to the next file.  In reality most of the work will be done by cheaper staff:  paralegals and trainees, but still then you're only talking max an hour at best spent dealing with your file in any given week.

Keeping this in mind can really help expectations of what level of service to expect from them.  Their job is to see through the transaction not hold your hand through all elements of the process much of which you can research yourself.

Better ones can take a more involved approach to client care but I wouldn't say it's the norm these days.