Consistency is a very key thing in tennis as it allows players to have longevity in the sport which is important if you want to regularly challenge for trophies.
Richard Gasquet hasn't been challenging for trophies for a while now even though he won one earlier this year in Auckland thanks to an epic choke by Cam Norrie in his hometown. The French player is one of the more consistent players on the Tour as he's still part of the 100 even after so many years.
His current streak stands at 925 consecutive weeks which is the longest streak out of all players in the top 100, including Djokovic. The newly-crowned Roland Garros champion has been in the sport for a long time and yet he's only at 914 consecutive weeks, 11 weeks behind Richard Gasquet. There are a few other active players with some impressive streaks regarding this topic and number four is Marin Cilic. He's been part of the top 100 for 794 weeks.
Then we have Grigor Dimitrov who has been part of the top 10 for 562 weeks and Roberto Bautista Agut at 543 weeks. All of these players are quite known for their consistency. Cilic has been able to make some deep runes every year which is good enough to keep himself in the top 100. Dimitrov is also a player who hasn't been winning trophies but every one and a while the Bulgarian finds a good result. Bautista Agut is pretty much identical in that regard.
All of these players including Gasquet have been able to avoid major injuries as well which is another crucial part. Sometimes you can't even hold your rank because you can't play and most of these were unable to avoid any major injuries in their careers.